maintenance FIAT PUNTO 1996 176 / 1.G User Guide

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Component location - diesel models ib-s
Rear underbody view - turbo diesel model
1
Fuel tank
2
Exhaust
tailpipe
and
silencer 3 Fear axle 4 Coil springs 5
Rear anti-roll bar

Handbrake cables
7
Rear brake pressure regulating valve
8
Rear shock
absorber
lower
mountings
Maintenance procedures
1 Introduction
This Chapter Is designed to help the home mechanic maintain his/her vehicle for safety, economy, long life and peak performance. The Chapter contains a master maintenance schedule, and Sections dealing specifically with each task in the schedule. Visual checks, adjustments, component renewal and other helpful items are included. Refer to the accompanying illustrations of the engine compartment and the underside of the vohicle for the locations of the various components. Servicing your vehicle in accordance with ihe mileage/time maintenance schedule and the following Sections will provide a planned maintenance programme, which should result in a long and reliable service life. This is a comprehensive plan, so maintaining some items but not others at the specified service internals, will not produce the same results. As you service your vehicle, you will ctecover that many of the procedures can. and should, be grouped together, because of the particular procedure being performed, or because of the proximity of two otherwise-unrelated components to one another. For example, if the vehicle is raised for any reason, the exhaust can be inspected at the same time as the suspension and steering components. The first step in this maintenance programme is to prepare yoursetf before the
actual work begins. Read through all the Sections relevant to the work to be carried out. then make a list and gather all the parts and tools required. If a problem is encountered, seek advice from a parts specialist, or a dealer service department.
2 Regular maintenance
1 If, from the time Ihe vehicle is new, the routine maintenance schedule is followed closely, and frequent checks are made of fluid levels and high-wear Items, as suggested throughout this manual, the engine wifl be kept in relatively good running condition, and the need for additional work will be minimised. 2 It is possible that there will be times when the engine is running poorly due to the lack of regular maintenance. This is even more likely if a used vehicle, which has not received regular and frequent maintenance checks, is purchased, in such cases, additions! work may need to be carried out, outside of the regular maintenance intervals. 3 If engine wear is suspected, a compression test {refer to Chapter 2C} will provide valuable information regarding the overall performance of the main internal components. Such a test can be used as a basis to decide on the extent of the work to be carried out. If, for example, a compression test indicates serious Internal engine wear, conventional maintenance as
described in this Chapter will not greatly improve the performance of the engine, and may prove a wa3te of time and money, unless extensive overhaul work Is carried out first. 4 The following series of operations are those usually required to Improve the performance of a generally poor-running engine:
Primary operations a,I Clean, Inspect and test the battery (See Weekly checks). b) Check all the engine-related fluids (See Weekly checks). c) Drain the water from the fuel filter (Section 4) d) Check the condition and tension of the auxiliary dnvebeft(s) (Section 16). e) Check the condition of the air fitter, and renew if necessary (Section 13). f) Check the condition of all hoses, and check for fluid leaks (Section 8). g) Check the engine idle speed setting {Section 11). h) Check the exhaust gas emissions (Section 25). 5 If the above operations do not prove fully effective, carry out the following secondary operations:
Secondary operations All items listed under Pnmary operations, plus the following: a) Check the charging system (Chapter 5A, Section 4). b) Renew the fuel filter (Section 12) and check the fuel system (see Chapter 4Q.

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ib.6 Maintenance procedures - diesel models
Every 5000 miles (7500 km) or 6 months
3 Engine oil and filter renewal it-
1 Frequent oil and filter changes are the most important preventative maintenance procedures which can be undertaken by the OlY owner. As engine oil ages, if becomes diluted and contaminated, which leads lo premature engine wear. 2 Befote starting this procedure, gather ail the necessary tools and materials. Also make sure that you have plenty of clean rags and newspapers handy, to mop up any splits. Ideally, the engine oil should be warm, as it will drain better, and more built-up sludge will be removed with it. Take care, however, not to touch the exhaust or any other hot parts of the engine when working under the vehicle. To avoid any possibility of scalding, and to protect yourself from possible skin irritants and other harmful contaminants in used engine oils, it is advisable to wear gloves when carrying out this woik. Access to the underside of the vehicle will be greatly improved if it can be raised on a lilt, driven onto ramps, or jacked up and supported on axle stands {see Jacking and vehicle support). Whichever method Is chosen, make sure that the vehicle remains level, or If it is at an angle, that Ihe drain plug is at the lowest point. 3 Slacken the drain plug about half a turn using a 12 mm Allen key (see Illustration) Position the draining container under the drain plug, then remove the plug completely (see Haynes Hint), 4 Allow some time for the oid oil to dram, noting that it may be necessary to reposition the container as the oil (tow slows to a trickle. 5 After all the oil has drained, wipe off the drain plug wilh a clean rag, then clean the area around the drain plug opening and refit the plug. Tighten the ptug securely. 6 If the filter is also to be renewed, move the container Into position under the oil filter, which Is located on the front right-hand side of the engine. 7 Using an oil filter removal tool if necessary, slacken the filter initially, then unscrew It by hand the rest of the way (see illustrations).
3.3 Using a 12 mm Allen key to loosen the engine oil drain plug
Empty the oil In (he old filter Into Ihe container. 8 Use a clean rag to remove all oil, dirt and sludge from the filter sealing area on the engine. Check the old lilter to make sure thai the rubber sealing ring has not stuck to the engine. If it has. carefully removo it. 9 Apply a light coating of clean engine oil to the sealing ring on the new filter, then screw it into position on the engine. Tighten the filter firmly by hand only • do not use any tools (see Illustration), 10 Remove Ihe old oil and all tools from under the vehicle then lower Ihe vehicle to the ground (If applicable). 11 Remove tho dipstick, then unscrew (he oil liiler cap from the cylinder head cover. Fill the engine, using Ihe correct grade and typo of oil (see Weekly checks). An oil can spout or funnel may help to reduce spillage Pour in half the specified quantity of oil first, then wait a few minutes for the oil to fall to the sump. Continue adding oil a smalt quantity at a time until Ihe level Is up to the MAX mark on the dipstick. Refit the filler cap. 12 Start the engine and run it for a tew minutes; check for leaks around the oil filter seal and the sump drain plug. Note that there may be a delay of a few seconds before the oil pressure warning light goes oul when the engine is first started, as the oil circulates through the engine oil galleries and the new oil filter before the pressure builds up.
Keep the drain plug pressed Into the sump while unscrewing It by hand the lost couple of turns. As the plug releases, move It away sharpty so that the stream of oil issuing from the sump runs Into the container, not up your sieeve.
13 Switoh off the engine, and wait a few minutes for Ihe oil to settle in the sump once mora. With the new oil circulated and the fitter completely full, recheck the level on Ihe dipstick, and add more oil as necessary. 14 Dispose ot the used engine oil safely, wilh reference lo General repair pioceduros In Ihe reference Sections of this manual.
4 Fuel filter water draining ^
1 A water drain screw is provided at the base of the fuel filter. 2 Position a suitable container under ihe fuel filter, Loosen Ihe bleed screw on the lop ol the filter, and open the drain screw at the base of tne filter by turning it anti-clockwise Allow fuel and water to drain until fuel, free from water, emerges from tho drain screw outlet. Close tne drain and bleed screws and tighten them securely 3 Dispose of the drained fuel safely. 4 Start tho onglno. II difficulty is experienced, Weed the fuel system (see Chapter 4C).
3.7a Using an oil fitter removal chain strap 3.7b Removing the oil filter 3.9 Now oil filter tightened by hand

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Maintenance procedures - diesel models ib.?
Every 10 000 miles (15 000 km) or 12 months
5 Brake warning lamp operation check 1
1 With Ihe ignition Key inserted and turned to the MAR position, open the bonnet and depress the button on the top of the brake
fluid
reservoir cap (see illustration). I
As
the button is pressed, the brake warning
lamp
on the instrument panel should light. 3 If Ihe lamp fails to illuminate, check the operation of the level switch using a continuity taster, then refer to Chapter t2, Section 5,
and
check the Instrument panel bulb.
6 Front brake pad check ^
I
1 firmly apply Ihe handbrake, then jack up the front of the car and support it securely on arie stands (see Jacking and vehicle support). Remove the front roadwheels. 2 Using a steel rule, measure the thickness of
the
friction material of the brake pads on both brakes. This must not be less than 1.5 mm. Ctefc the thickness of the pad friction material through the hole on the front of the caliper
|see
lustration), 3
For a
comprehensive check, the brake pads should be removed and cleaned. The operation of the caliper can then also bo checked, and the condition of the brake disc iteeil can be fully examined on both sides. Refer to Chapter 9 for further Information. 4 If any pad's friction material Is worn to the specified thickness or less, all lour pads must to renewed as a set. Refer to Chapter 9. 5 On completion refit the roadwheels and lower the car to the ground.
7 Underbody sealant check f^
1 Jack up the front and rear of the car and support on axle stands (see Jacking and
vehicle
support). Alternatively position the car over
an
Inspection pit. 2 Check the complete underbody, wheel housings and side sills for corrosion and/or damage to the underbody sealant. If evident,
rapairi

8
Hose
and fluid leak check
1 Visually inspect the engine Joint faces. g3skets and seals for any signs of water or oil leaks. Pay particular attention to the areas
5.1 Depress tho button on the top of the brake fluid reservoir cap
around the camshaft cover, cylinder head, oil filter and sump joint faces. Bear in mind that, over a period of time, some very slight seepage from these areas is to be expected -what you are really looking for is any indication of a serious leak (see Haynes Hint). Should a teak be found, renew the offending gasket or oil seal by referring to the appropriate Chapters In this manual, 2 Also check the security and condition of all the engine-related pipes and hoses. Ensure thai all cable-ties or securing clips are In place and in good condition. Clips which are broken or missing can lead to chafing of the hoses, pipes or wiring, which could cause more serious problems In the future. 3 Carefully check the radiator hoses and heater hoses along their entire length. Renew any hose which is cracked, swollen or deteriorated. Cracks will show up better If the hose is squeezed. Pay close attention to the hose clips that secure the hoses to the cooling system components. Hose clips can pinch and puncture hoses, resulting in leaks. 4 Inspect all the cooling system components (hoses. )olnt faces etc.) for leaks. A leak in the cooling system will usually show up as white or rust-coloured deposits on the area adjoining the leak, Where any problems of this nature are found on system components, renew the component or gasket with reference to Chapter 3. 5 With the vehicle raised, inspect the fuel tank and filler neck for punctures, cracks and other damage, The connection between the filler neck and tank is especially critical. Sometimes a rubber filler neck or connecting hose will leak due to loose retaining clamps or deteriorated rubber. 6 Carefully check all rubber hoses and metal fuel lines leading away from the fuel tank. Check for loose connections, deteriorated hoses, crimped lines, and other damage. Pay particular attention to the vent pipes and hoses, which often loop up around the filler neck and can become blocked or crimped. Follow the lines to the front of the vehicle, carefully Inspecting them all the way. Renew damaged sections as necessary.
6.2 Check the thickness of the pad friction material through the hote on the front of the caliper
7 With the vehicle raised, check along the length of the underside for leaks from the metal brake lines, caused by damage or corrosion. 8 At each front brake caliper, check the area around the brake pipe unions and the bleed nipples for hydraulic fluid leakage, 9 Remove the front roadwheels and chock for fluid leakage from the area around the caliper piston seal. Check that the tip of the piston dust seal is correctly located in its groove. If it has been displaced, the brake caliper should be removed and overhauled as described in Chapter 9, to check for internal dirt Ingress or corrosion. 10 Check the area surrounding the master cylinder and vacuum servo unit for signs of corrosion, Insecurity or hydraulic fluid leakage. Examine the vacuum hose leading to the servo unit for signs of damage or chafing. 11 From within the engine compartment, check the security of all fuel hose attachments and pipe unions, and Inspect the fuel hoses and vacuum hoses for kinks, chafing and deterioration. 12 Where applicable, check the condition of the power steering fluid hoses and pipes.
A leak in the cooling system will usually show up as white or rust coloured deposits on the area adjoining the leak.

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Maintenance procedures - diesel models 1B.13
Every 60 000 miles (90 000 km) or 6 years
Refer to Chapter 40. A full chock of the 26 Emissions control systems emissions control systems must be made by a check Fiat dealer.
Every 80 000 miles (120 000 km)
26 Manual transmission ,v->> oil renewal K
1 Pak the vehicle on a level surface, if possible over an inspection pit or on a ramp as the filer/level and drain plugs are accessed from
under the
engine compartment, ff necessary tack up Ihe vehicle and support on axle stands (see Jacking and
vehicle
support). 2
Wipe
clean the area around the filler/! a vol and vain plugs, which are situated on the front and bottom of the transmission (see Illustration}.
3 Using an Allen key, unscrew the fillor/level plug and clean it. 4 Position a suitable container beneath the transmission, then use the Allen key to unscrew the drain plug. Allow the oil to completely dram. 5 Wipe clean the drain plug then refit and tighten It. 6 Fill the transmission with the correct grade and quantity of oil, referring to Section 22 when checking the level. Refit and tighten the filler/level plug. 7 Where applicable lower the vehicle to the ground. 26.2 Transmission drain plug location (viewed from undor tho vohlcle)
Every 2 years (regardless of mileage)

27
Coolant renewal St I
Coo//ng system draining

A


Warning: Wait until the engine is coid before starting this procedure. Do not allow anti-fnue to come in contact with your skin, or with the painted surfaces of the vehicle.
Rinse
off spills immediately with plenty of water. Never leave antifreeze lying around fh an open container, or in a puddle in the driveway or on the garage floor. Children
and
pets are attracted by Its sweet smell,
bat
antifreeze can be fatal if ingested. 1 With the engine completely cold, cover the expansion tank cap with a wad of rag, and slowly turn the cap anti-clockwise to relieve the
pressure in the cooling system (a hissing sound will normally be heard). Wail until any pressure remaining in the system is released, then continue to turn the cap until it can be removed. 2 Position a suitable container beneath the radiator bottom hose connection, then release the retaining clip and ease the hose from the radiator stub (see Illustration), If the hose joint has not been disturbed for some time, it will be necessary to gently manipulate the hose to break the joint. Do not use excessive force, or the radiator stub could be damaged. Allow the coolant to drain into the container. 3 Certain models are fitted with cooling system bleed plugs, which should be opened to aid the draining process and help prevent airlocks. These are located on the heator Inlet hose and on the top right hand edge of the radiator (see Illustrations), ff the coolant has
been drained for a reason other than renewal, then provided It is clean and less than two years old, it can be re-used, though this is not recommended. 4 Once all the coolant has drained, reconnect the hose to the radiator and secure it in position with the retaining clip.
Cooling system flushing 5 If coolant renewal has been neglected, or if the antifreeze mixture has become diluted, then In time, the cooling system may gradually lose efficiency, as the coolant passages become restricted due to rust, scale deposits, and other sediment. The cooling system efficiency can be restored by flushing tho system clean. 6 The radiator should be (lushed independently of the engine, to avoid unnecessary contam-ination.
27.2 Disconnecting the radiator bottom hose to drain the coolant 27.3a Location of cooling system bleed plugs (arrowed) 27.3b Bleed screw located on the top right hand edge of the radiator

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2D*10 Engine removal and overhaul procedures
1 General information
Included In (his Part of Chapter 2 are details of removing the engine/transmission from the car and general overhaul procedures for tho cylinder head, cylinder block/crankca9e and all other engine internal components. The information given ranges from advice concerning preparation for an overhaul and the purchase of replacement parts, to detailed step-by-step procedures covering removal, inspection, renovation and refitting of engine Internal components. After Section 5, all instructions are based on the assumption that the engine has been removed from the car. For Information concerning in-car engine repair, as well as the removal and refitting of those external components necessary for full overhaul, refer to Part A, 8 or C of this Chapter (as applicable) and to Section 5. Ignore any preliminary dismantling operations described in Part A. B or C that are no longer relevant onca the engine has been removed from ihe car.
2 Engine overhaul -general information
1 It Is not always easy to determine when, or if, an engine should be completely overhauled, as a number of lectors must be considered. 2 High mileage Is not necessarily an Indication that an overhaul Is needed, while low mileage does not preclude the need for an overhaul. Frequency of servicing Is probably the most important consideration. An engine which has had regular and frequent oil and filter changes, as well as other required maintenance, should give many thousands of miles of reliable service. Conversely, a neglected engine may require an overhaul very early In its life. 3 Excessive oil consumption Is an Indication that piston rings, vaivo seals and/or valve guides are in need of attention. Make sure that oil leaks are not responsible before deciding that the rings and/or guides are worn Perform a compression test, as described In Parts A or B (petrol engines) or C (diesel engines) of this Chapter, to determine the likely cause of the problem. 4 Check the oil pressure with a gauge fitted In place of the oil pressure switch. If it Is extremely low. the main and big-end bearings, and/or the oil pump, are probably worn out. 5 Loss of power, rough running, knocking or metallic engine noises, excessive valve gear noise, and high fuel consumption may also point to Ihe need for an overhaul, especially if
they are all present at the same time. If a complete service does not remedy the situation, major mechanical work is the only solution. 6 An engine overhaul involves restoring ell Internal parts to the specification of a new engine. During an overhaul, the cylinders are rebored (where applicable), the pistons and the piston rings are renewed. New main and big-end bearings are generally fitted; If necessary, the crankshaft may be reground. to restore the journals. 7 The valves are also servrced as well, since they are usually In less-than-perfect condition at this point. While the engine is being overhauled, other components, such as the starter and alternator, can be overhauled as well. The end result should be an as-new engine that will give many trouble-free miles. Note: Critical cooling system components such as the hoses, thermostat and coolant pump should be renewed when an engine is overhauled. The radiator should be checked carefully, to ensure that it is not clogged or leaking. A/so. it Is a good Idea to renew the ofI pump whenever the engine i$ overhauled.
8 Before beginning the engine overhaul, read through tho entire procedure, to familiarise yourself with the scope and requirements of the job. Overhauling an engine is not difficult If you follow carefully all of the instructions, have the necessary tools and equipment, and pay close attention to all specifications. It can, however, be time-consuming. Plan on the car being off the road for a minimum of two weeks, especially If pans must be taken to an engineering wo'kd for repair or reconditioning.
9 Check on the availability of parts and make sure that any necessary special tools and equipment are obtained in advance. Most work can be done with typical hand lools, although a number of precision measuring tools are required (or Inspecting parts to determine if they must be renewed. Often the engineering works will handle the inspection of parts and offer advice concerning reconditioning and renewal, Note: Always wait unt'l the engine has been completely dismantled, and until all components (especially the cylinder block/crankcase and the crankshaft) have been inspected, before deciding what service and repair operations must be performed by an engineering works. The condition of these components will be the major factor to consider when determining whether to overhaul the original engine, or to buy a reconditioned unit. Do not. fh ere tore, purchase parts or have overhaul work done on other components until they have been thoroughly Inspected. As a general rule, time is the primary cost of an overhaul, so it does not pay to fit worn or sub-standard parts.
10 As a final note, to ensure maximum life and minimum trouble from a reconditioned engine, everything must be assembled wilh care, in a spotlessly-clean environment.
3 Engine and transmission removal -methods
and
precautions
1 If you have decided that the engine must be removed for overhaul or major repair work, several preliminary steps should be taken. 2 Locating a suitable place to work is extremely important. Adequate work space, along with storage space for the car, will be needed. If a workshop or garage Is not available, at the very least, a flat, level, clean work surface Is required. 3 Cleaning the engine compartment and engine/transmission before beginning the removal procedure wilt help keep tools clean and organised. 4 An engine hoist or A-frame will also be necessary. Make sure the equipment is rated In excess of the combined weight of the engine and transmission, Safety Ib of primary Importance, considering the potential hazards involved in lifting the engine/transmission out of the car. 5 If this is Ihe first time you have removed
an
engine, an assistant Bhould Ideally be available. Advice and aid from someone more experienced would also be helpful. There are many instances when one person cannot simultaneously perform all of the operations required when lifting the engine out of Ihe vehicle. 6 Plan the operation ahead of time. Before starting work, arrange for the hire of or obtain all of the tools and equipment you will need. Some of the equipment necessary to perform engine/transmission removal and Installation safely and wilh relative ease On addition to an engine hoist) Is as follows: a heavy duly trolley jack, complete sets of spanners and sockets as described in the reference section of this manual, wooden blocks, and plenty of rags and cleaning solvent for mopping up spitted oil, coolant and fuel. If the hoist must be hired, make sure that you arrange for it In advance, and perform all of the operations possible without it beforehand. This will save you money and time.
7 Plan for the car to be out of use for quite a while. An engineering works will be required to perform some of the work which the do-it-yourselfer cannot accomplish without special equipment. These places often have a busy schedule, so it would be a good idea to consul! them before removing the engine, in order to accurately estimate the amount of time required to rebuild or repair components that may need work, 9 Always be extremely careful when removing and refitting the engine/transmission. Serious injury can result from careless actions. Plan ahead and take your time, and a job of this nature, although major, can be accomplished successfully.

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4A*2 Fuel system - single-point petrol Injection models
1 The luel system referred to In this Section is defined as the tank-mounted fuel pump, the fuel litter, the throttle body and pressure regulator components, and the metal pipes and flexible hoses of the fuel lines between these components. All ihese contain fuel which will be under pressure while the engine Is running and/or while tha Ignition is switched on. The pressure will remain for some time after tho ignition has been switched off, and must be relieved before any of these components are disturbed (or servicing work. 2 Disconnect the battery negative terminal (refer to D/sconnecf/ngr the battery in the Reference Section of this manual), 3 Place a container beneath the relevant connection/union to be disconnected, and have a large rag ready to soak up any escaping fuel not being caught by the container. 4 Slowly loosen the connection or union nut (as applicable) to avoid a sudden release of pressure, and wrap tho rag around the connection to catch any fuel spray which may be expelled. Once the pressure is released, disconnect the fuel line, and Insert plugs to minimise fuel loss and prevent the entry of dirt Into the fuel system.
9 Inlet manifold -removal and refitting ^
Note: Refer to the warning given In Section 1 before proceeding.
Removal 1 Remove the throttle body assembly as described in Section 5. 2 Drain the cooling system as described in Chapter 1A. 3 Disconnect the winng connector from the coolanl temperature sensor (situated on the left-hand sidB of the manifold). 4 Undo the bolt securing the accelerator cable mounting bracket to the manifold, and position it clear of the manifold. 5 Slacken the retaining clip and disconnect tha coolant hose from the rear of the manifold. 6 Disconnect the brake vacuum hose. 7 Undo the seven manifold retaining nuts and
10.2 The diagnostic connector la located behind the ECU bolts, and remove (he manifold from the engine. Remove the gasket and discard It; a new one should be used on refitting.
Refitting 8 Refitting is a reverse of the removal procedure, noting the following points: a) Ensure that the manifold and cylinder head mating surfaces are clean and dry, and fit a nev/ manifold gasket. Refit the manifold and securely tighten Its retaining nuts. b) Ensure that all relevant hoses are reconnected fo their original positions and are securely held (where necessary) by the retaining clips. c) Refit the throttle body assembly with reference to Section S. d) On completion, refill the cooling system as described In Chapter 1A.
correctly adjusted, and that the engine breather hoses are clear and undamaged. 2 If these checks fall to reveal the cause of the problem, the vehicle should be taken to a suitably-equipped Fiat dealer for testing. A wiring block connector Is Incorporated In the engine management circuit, into which a special electronic diagnostic tester can be plugged; the connector is situated behind the ECU (see Illustration). The tester will locate the fault quickly and simply, alleviating the need to test all the system components Individually, which is a time-consuming operation that carries a high risk of damaging the ECU.
Adjustments 3 As mentioned above, the idle speed and mixture adjustment are all monitored and controlled by the ECU, and are not adjustable Experienced home mechanics with a considerable amount of skill and equipment (including a good-quality tachometer and a good-quality, carefully calibrated exhaust gas analyser) may be able to check the exhaust CO level and ihe idle speed. However, If thes* are found lo be in need of adjustment, the car must be taken to a suitably-equipped Flat dealer for testing using the special test equipment which is plugged into the diagnostic connector.
11 Unleaded petrol -general Information and usage
10 Fuel injection system - & testing and adjustment S
Testing 1 If a fault appears in the fuel injection system, first ensure that all the system winng connectors are securely connected and free of corrosion. Then ensure that the fault Is not due to poor maintenance; ie, check that the air cleanor fitter element is clean, the spark plugs are In good condition and correctly gapped, that tho valve clearances are
Note: The information given in this Chapter
is
correct at the time of writing. If updated Information is thought to be required, check with a Fiat dealer. If travelling abroad, consult one of the motonng organisations (or a similar authority) for advice on the fuel available. 1 All petrol models are fitted with a catalytic converter and must be run on unleaded fuel only - the fuel recommended by Flat is given In the Specifications of this Chapter. Under no circumstances should leaded fuei (UK 4-slar) be used, as this may damage the converter. 2 Super unleaded petrol (98 octane) can also be used in all models if wished, though there is no advantage in doing so.

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4A*2 Fuel system -
single-point
petrol Injection models
1 General information and precautions
General information The
LAW
Weber-Maretil multi-point Injection (MPI) system is a self-contained engine management system, which controls both the fuel injoction and Ignition (see Illustrations). This Chapter deals with the fuel Injection system components only - refer to Chapter 5B for details of the ignition system components. The fuel injection system comprises a fuel tank, an electric fuel pump, a fuel filter, fuel supply end return lines, a throttle body, a fuel rail with four electronic Injectors, and an Electronic Control Unit (ECU) together with its associated sensors, actuators and wiring. On pre-1998, 8-valve engines and all 16-valve engines, the fuel pump delivers a constant supply of fuel through a cartridge filter to the fuel rail, and the fuel pressure regulator (located on Ihe fuel rail) maintains a constant fuel pressure at the fuel Injectors and returns excess fuel to the tank via the return
line, This constant flow system also helps to reduce fuel temperature and prevents vaporisation. On later 8-valve engines, a returnless fuel system is used. With this arrangement, the fuel filter and fuel pressure regulator are an integral part of the fuel pump assembly located In the fuel tank. The regulator maintains a constant fuel pressure in the supply line lo the fuel rail and allows excess fuel to recirculate in the fuel tank, by means of a bypass channel, if the regulated fuel pressure is exceeded. As the fuel filler Is an integral part of the pump assembly, fuel filter renewal Is no longer necessary as part of the maintenance and servicing schedule. The fuel injectors are opened and closed by an Electronic Control Unit (ECU), which calculates the Injection timing and duration according to engine speed, throttle position and rate of opening, inlet air temperature, coolant temperature and exhaust gas oxygen content information, received from sensors mounted on the engine. The injectors are operated simultaneously (le not sequentially) and Inject half of the quantity of fuel required on each turn of the crankshaft. Inlet air Is drawn into the engine through
the air cleaner, which contains a renewable paper filter element. On 8-valve engines, the Inlet air temperature is regulated by a vacuum operated valve mounted in the air ducting, which blends air at ambient temperature with hot air, drawn Irom over the exhaust | manifold. Idle speed Is controlled by a stepper motor 1 located on the side of the throttle body. Cold storting enrichment is controlled by the ECU using the coolant temperature and Inlet air temperature parameters to Increase the Injector opening duration. The exhaust gas oxygen content it constantly monitored by the ECU via the Lambda/oxygen sensor, whioh Is mounted in the exhaust downpipe. The ECU then uses this Information to modify the Injection timing and duration to maintain the optimum air/fuel ratio. An exhaust catalyst is fitted to all models. The ECU also controls the operation of the activated charcoal filler evaporative loss system - refer to Chapter 4D for further details. It should be noted that fault diagnosis of the IAW Weber-Marelll system Is only possible with dedicated electronic test equipment.
1.1a IAW Weber-Marelii multt-point Injection (MPi) system (8-valve engines) f Fuel
tank
7 Air
cleaner
13 Coolant temperature sensor 19 Diagnostic socket 2 Fuel pump 8 Fuel vapour trvp 14 Intake air temperature 20
EVAP
solenoid 3 Filter (pre-1998 models) 9 Idle control stepper motor sensor 21 Lambda/oxygen sensor 4 Fuel
rail
10 Manifold absolute pressure 15 Duel
relay
22 Rev counter 5 Pressure regulator
(pre-1998
sensor 16 Ignition colls 23 IAW failure warning light models)
11 ECU
17 Rpm and TDC sensor 24 Anti-refhjx
valve
6 Injectors 12 Throttle position sensor 18 Spark piugs

Page 137 of 225


Fuel system - diesel models 4C*3
Torque wrench settings Nm Ibfft Fuel injection pump roar bracket .. . 29 21 Fuel Injection pump .... 25 18 Fuel Injectors 41 Fuel pipe union nuts .... 30 22 Inlet manifold .... 24 18 Lower oil tiller mounting and injection pump mounting nut ..... .... 71 S2 Turbocnarger to exhaust manifold .... <10 30 Upper Dtl filter mounting end injection pump mounting nut 98 72
1 General information and precautions
General information The fuel system consists of a rear-mounted fust tank, a fuel filter with integral water separator, a fuel injection pump, in|eciors and associated components. A turbocharger is fitted to TDS, TD and TDSX models. Fuel Is drawn from the fuel tank to the fuel Injection pump by a vane-type transfer pump Incorporated in the fuel injection pump. Before reaching tho pump, the fuel passes through a fuel filter, where foreign matter and water aro removed. Excess fuel lubricates the moving components of the pump, and Is then returned to the tank. On turbo models with the Bosch fuel Injection systom, an eiectncally operated heater is incorporated In the fuel filter housing. The fuel injection pump is driven at half-crankshaft speed by the timing belt. The nigh pressure required to inject tho fuel into the compressed air in the swirl chambers Is achlovod by a cam plate acting on a single piston on the Bosch pumo, or by two opposed pistons forced together by rollers running in a cam ring on the Lucas (CAV) pump. Tlie fuel passes through acentral rotor with a single outlet drilling which aligns With ports leading to the Injector pipes. Fuel metering is controlled by a centrifugal governor, which reacts to accelerator pedal
position end engine speed. The governor is linked lo a metering valve, which increases or decreases the amount of fuel delivered at each pumping stroke. On turbocharged models, a separate device also Increases luel delivery with increasing boost pressure. Basic injection timing is determined when the pump is fitted. When the engine is running, it Is varied automatically to suit the prevailing engine speed by a mechanism which turns the cam plate or ring, Tho four fuel injectors proouco a homogeneous spray of fuel Into the swirl chambers located In the cylinder head. The Injectors are calibrated to open end close at critical pressures lo provide efficient and even combustion. Each injector needle is lubricated by fuel, which accumulates In the spring chamber and is channelled to the injection pump return hose by loak-off pipes Bosch or Lucas fuel system components mBy be fitted, depending on the model. Components from the latter manufacturer are marked either CAV. Roto-dlesel or Con-diesel. depending on their date and place of manufacture. With the exception of the fuel filter assembly, replacement components must be of tho same make as those originally fitted. Cold starting is assisted by preheater or glow plugs fitted to each swirl chamber. On the Bosch injection pump, an automatic cold Injection advance device operated through a thermal switch, advances the injection timing by Increasing the fuel pressure. The device operates at coolant temperatures below 55° C,
A stop solenoid cuts the fuel supply to V* Injection pump rotor when the ignition i switched off (see illustration) Provided that the specified maintenance* earned out. the fuel injection equipment #» give long and trouble-free service, ft* j injection pump itself may well outlast tlx ' engine, The main potential cause of damage j to the injection pump and injectors is dirt e water in the fuel. 1 Servicing of the injection pump and injectwi: j, is very limited for tho home mechanic, antf dismantling or adjustment other than thtf described In this Chapter must be entrusted to ' a Rat dealer or fuel Injection specialist.
Precautions

A


Warning: It Is necessary to takt I certain precautions when woriong , on the fuel system component^ particularly the fuel Injectors. Befon carrying out any operations on tho fuel system, refer to the precautions given* Safety first! at the beginning of Mis manual, and to any additional wamlrq notes at the start of the relevant
Sections.

2 Air cleaner and inlet system ^ • removal and refitting S
Removal 1 Remove the air cleaner element u described In Chapter 1B (see illustration).
1.9 Stop solenoid on the injection pump 2.1 Releasing the air cleaner cover clips

Page 146 of 225


4D*3 Exhaust and emission control systems
Refitting 8 Refitting is a reversal of the removal pro-cedure but fit new gaskets. Tighten the nuts lo the specified torque.
Diesel models Note: On diesel models the inlet and exhaust
manifolds
are located on the rear of the engine
end
share the same securing nuts and gasket. Removal 8 Remove the inlet manifold as described In Part
C
of this Chapter. 10 Firmly apply the handbrake, then jack up lite front of tho car and support it securely on axle stands (see Jacking and vehicle support). 11 Straighten the tab washers (where fitted), then unscrew and remove the exhaust downpipe retaining nuts. Detach the downpipe from the manifold/turbocharger. Suitably support the downpipe. 12 Undo the manifold-to-cylinder head securing nuts and withdraw the manifold (see Illustration). 13 Separate the turbocharger from the manifold with reference to Chapter 4C. 14 Remove the gasket and clean the mating
(aces
of the manifold, cylinder head and down-pipe flange (see illustration). The gasket must
be
renewed when refitting the manifold, Refitting
15 Refitting is a reversal of the removal procedure but fit a new gasket. Tighten the retaining nuts to the specified torque and where necessary lock them by bending over
the
tocktabs.
6 Exhaust system - % general information and ^ component renewal
Genera/ Information 1 A three section exhaust system is fitted consisting of a twin-branch front downpipe, a catalytic converter, and a tailpipe with two silencers. The downpipe-to-manifold and downpipe-to-catalytic converter joints are both of flange and gasket type, whereas the remaining joint Is of the sleeve type secured
witn
a clamp ring (see illustration). 2 The system is suspended throughout its entire length by rubber mountings.
Removal 3 Each exhaust section can be removed individually or, alternatively, the complete system can be removed as a unit. Where separation of the rear sleeve Joint is necessary, it may be more practical to remove
the
entire system rather than try and separate
the Joint
In position. 4 To remove the system or part of the system, first jack up the front of the vehicle and support on axle stands (see Jacking and nhlcle support), Alternatively position the
vehicle
over an inspection pit or on car ramps.
5.12 Removing the exhaust manifold (diesel engine) Downpipe 5 Support the catalytic converter using an axle stand or blocks of wood. Where applicable on petrol models, refer to Section 4 and remove the oxygen sensor from the exhaust downpipe. 6 Unscrew and remove the bolts securing the downpipe to tha catalytic converter, then separate the joint and recover the gasket. 7 Bend back the locktabs (where fitted) then unscrew the nuts securing the downpipe to the exhaust manifold/turbocharger. and lower the downpipe, Recover the gasket. Catalytic converter
8 Support the tailpipe section of the exhaust using an axle stand or blocks of wood. 9 Unscrew and remove the bolts securing the downpipe to the catalytic converter, then separate the joint and recover the gasket. 10 Unscrew the clamp bolt and separate the converter from the tailpipe section. 11 Release the mounting rubber and remove the converter from under the vehicle. Tailpipe and silencers 12 Support the catalytic converter using an axle stand or blocks of wood. 13 Unscrew the clamp bolt and separate the catalytic converter from the tailpipe section. 14 Release the tailpipe section from its mounting rubbers and remove from under the vehicle. Complete system 15 Disconnect the downpipe from the ex-haust manifold as described in paragraph 7.
6.1 Exhaust clamp ring securing the tailpipe to the front exhaust system
5.14 Removing the oxhaust manifold gasket (diesel engine) 16 With the aid of an assistant, free the system from all its mounting rubbers and manoeuvre it out from underneath the vehicle. Heatshield 17 The heatshield is secured to the underbody by bolts and Is easily removed once the exhaust system has been removed.
Refitting 18 Each section is refitted by a reverse of the removal sequence, noting the following points. a) Ensure that all traces of corrosion have been removed from the flanges and renew ail necessary gaskets. b) Inspect the rubber mountings for signs of damage or deterioru tion and renew
as
necessary. c) Before refitting the tailpipe joint, smear some exhaust system jointing paste to the joint mating surfaces to ensure an air-tight seal. Tighten the clamp bolt. d) Prior to fully tightening the rear joint damp, ensure that all rubber mountings are correctly /ocafed and that there is adequate clearance between the exhaust system and vehicle underbody.
7 Catalytic converter -general information and precautions
The catalytic converter is a reliable and simple device which needs no maintenance In itself, but there are some facts of which an owner should be aware if the converter is to function properly for its full service life.
Petrol models a) DO NOT use leaded petrot In a car equipped with a catalytic converter - Ihe lead will coat the precious metals, redudng their converting efficiency
and
will eventually destroy the converter. b) Always keep the ignition and fuel systems well-maintained in accordance with the manufacturer's schedule. c) If the engine develops a misfire, do not drive the car at all (or at least as little
as
possible) until the fault is cured.

Page 149 of 225


5A«2 Starting and charging systems
1 General information and precautions
General information The engine electrical system consists mainly of the charging and starting systems. Because of their engine-related functions, these components are covered separately from the body electrical devices such as the Ilght3, Instalments, etc (which are covered In Chapter 12). On petrol engine models refer to Part B for information on the ignition system, and on diesel models refer to Part C for information on the preheating system. The electncal system Is of 12-volt negative earth type. The battery fitted as original equipment is of maintenance* free (sealed for life} type and Is charged by the alternator, which is belt-driven from the crankshaft pulley. If a non-original battery is fitted It may be of standard or low maintenance type. The starter motor is of the pre-engaged type Incorporating an integral solenoid. On starting, the solenoid moves the drive pinion into engagement with the flywheel ring gear before the starter motor is energised. Once the engine has started, a one-way clutch prevents the motor armature being driven by the engine until the pinion disengages from the flywheel.
Precautions Further details of the various systems are given In the relevant Sections of this Chapter. While some repair procedures are given, the usual course of action is to renew the component concerned. The owner whose interest extends beyond mere component renewal should obtain a copy of the Automobile Electrical & Electronic Systems Manual, available from the publishers of this manual It Is necessary to take extra care when working on the electrical system to avoid damage to semiconductor devices (diodes and transistors), and to avoid the risk of personal injury. In addition to the precautions given in Safety first! at the beginning of this manual, observe the following when working on the system: Always remove rings, watches, etc before working on the electrical system. Even with the battery disconnected, capacitlve discharge could occur If a component's live terminal is earthed through a metal object. This could cause a shock or nasty bum. Do not reverse the battery connections. Components such as the alternator, electronic control units, or any other components having semi-conductor circuitry could be irreparably damaged. If the engine is being started using jump leads and a slave battery, connect the batteries positive-to-posibve and negative-to-
negative (see Jump starting). This also applies when connecting a battery charger but In this case both of the battery terminals should first be disconnected. Never disconnect the battery terminals, the alternator, any electrical wiring or any test Instalments when the engine Is running. Do not allow the engine to turn the alter-nator when the alternator Is not connected. Never test for alternator output by flashing the output lead to earth. Never use an ohmmeter ot the type Incorporating a hand-cranked generator for circuit or continuity testing. Always ensure that the battery negative lead is disconnected when working on the electrical system. Before using electric-arc welding equipment on the car, disconnect the battery, alternator and components such as the fuel Injection/ignition electronic control unit to protect them from the risk of damage. Several systems fitted to the vehicle require battery power to be available at all times, either to ensure their continued operation (such as the clock) or to maintain control unit memories or security codos which would be wiped if the battery were to be disconnected. To ensure that there are no unforeseen consequences of this action. Refer to Disconnecting the battery In the Reference Section of this manual for further Information.
2 Battery- % testing and charging
Standard and tow maintenance battery - testing 1 If the vehicle covers a small annual mileage, it is worthwhile checking the specific gravity of the electrolyte every three months to determine the state of charge of the battery. Use a hydrometer to make the check and compare the results with the following table, Note that the specific gravity readings assume an electrolyte temperature of 15*C (60'F); for every 10*C (18°f) below 158C (60aF) subtract 0.007, For every 108C (16'F) above 15"C (60'F) add 0.007. Ambient temperature Above 26"C Below 25DC Charged 1,210 to 1£30 1,270 to 1.290 70% charged 1.170to1.l90 1.230to1.250 Discharged 1.050toJ.070 1.110 to 1.130 2 If the battery condition is suspect, first check the specific gravity of electrolyte In each cell. A variation of 0.040 or more between any cells indicates loss of electrolyte or deterioration of the internal plates. 3 If the specific gravity variation is 0.040 or more, the battery should be renewed. If the cell variation Is satisfactory but the battery is discharged, it should be charged as described later in this Section.
Maintenance-free battery -testing 4 In cases where a sealed tor life maintenance-free battery is fitted, topplng-up and testing of the electrolyte in each cell Is not possible. The condition of the battery can therefore only be tested using a battery condition Indicator or a voltmeter. 5 Certain models may be fitted with a maintenance-free battery with a built-in charge condition Indicator. The indicator Is located in the top of the battery casing, and indicates the condition of the battery from its colour. If the Indicator shows green, then the battery is In a good state of charge. If the Indicator turns darker, eventually to black, then the battery requires charging, as described later in this Section. If Ihe indicator shows clear/yellow, then the electrolyte level in Ihe battery is too low to allow further use, and tho battery should be renewed. Do not attempt to charge, load or Jump start a battery when the indicator shows dear/yellow. 6 If testing the battery using a voltmeter, connect the voltmeter across the battery and compare the result with those given In the Specifications under 'charge condition'. The test is only accurate if the battery has not been subjected to any kind of charge for the previous six hours. If this is not the esse, switch on the headlights for 30 seconds, then wait four to five minutes baforo testing the battery after switching off the headlights. All other electrical circuits must be switched off, so check that the doors and tailgate are fully shut when making the test, 7 It the voltage reading Is less than 12.2 voHs, then the battery Is discharged, whilst a reading of 12.2 to 12.4 volts indicates 8 partially discharged condition. 6 If the battery Is to be charged, remove It from the vehicle (Section 3) and charge it as described later In this Section.
Standard and low maintenance battery - charging Note: The following is Intended as a guide only. Always refer to the manufacturer's recommendations (often printed on a label attached to the battery) before charging a battery. 9 Charge the battery at a rate of 3.5 to 4 amps and continue to charge the battery at this rate until no further rise In specific gravity Is noted over a four hour period. 10 Alternatively, a trickle charger charging at the rate of 1.5 amps can safely be used overnight. 11 Specially rapid boost charges which are claimed to restore the power of the battery in t to 2 hours are not recommended, as they can cause serious damage to the battery plates through overheating, 12 While charging the battery, note that the temperature of the electrolyte should never exceed 37.8*C(100°F),

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