steering FORD FESTIVA 1991 Owner's Guide

1. Position new gasket on exhaust manifold, and install turbocharger onto studs. Install 4 retaining nuts and tighten to specification. See
TORQUE SPECIFICATIONS
table at end of article.
2. Remove oil supply line from turbocharger. Position new (2-piece) exhaust gasket on cylinder head with heavy gasket installed first .
Carefully position turbocharger assembly in engine compartment and slide exhaust manifold on studs. Position heater tube bracket onto
exhaust stud. Install 11 retaining nuts onto exhaust manifold and tighten to specification. See TORQUE SPECIFICATIONS
table at
end of article. Tighten heater tube clamp bolt securely.
3. Raise vehicle. Position new gasket and install 2 retaining bolts on heater tube outlet. Install 2 retaining bolts into turbocharger support
bracket and tighten bolts to specification.
4. Connect coolant return hose. Connect oil return hose and secure with clamp. Position exhaust pipe onto turbocharger, and start nuts
and washers. Install 2 retaining bolts on exhaust hanger at engine. Slide on 2 rubber exhaust hangers at catalytic converter. Tighten
exhaust pipe retaining nuts to specification. Lower vehicle.
5. Install retaining bolt and brass washers on oil supply line, carefully position oil line into vehicle and hand-start bolt into engine block.
Connect and finger tighten oil line to turbocharger. Tighten oil line bolt and oil supply line on turbocharger to specification.
6. Connect coolant supply hose. Position air cleaner duct tube on turbocharger and tighten clamp. Install 2 screws retaining air cleaner
duct tube. Position power steering pump bracket on engine, and install 2 retaining bolts and one retaining nut. Tighten to specification.
Position power steering pump on mounting bracket, and install though bolt and adjuster. Connect lower radiator hose. Install power
steering belt. Position upper heat shield and install 2 retaining bolts finger tight.
7. Position lower heat shield and install three retaining bolts finger tight. Tighten all heat shield bolts to specification. Connect O2 sensor
and install connector into its retaining clip. See TORQUE SPECIFICATIONS
table at end of article. Position intercooler hose on
turbocharger and secure with clamp. Install throttle body air intake tube. Connect negative battery cable. Refill cooling system.
CYLINDER HEAD
Removal (1.3L)
1. Disconnect battery ground cable. Mark and disconnect fuel lines at fuel pump. Remove accessory belts, water pump pulley, crankshaft
pulley, timing belt covers, timing belt tensioner, timing belt, valve cover and exhaust and intake manifolds. Drain cooling system.
2. Mark and remove electrical connectors and vacuum hoses. Remove spark plug wires from spark plugs, and remove spark plugs. Remove
distributor cap. Disconnect vacuum hoses and distributor wiring.
3. Index distributor-to-mount position and remove hold-down bolt. Remove distributor assembly. Remove engine ground strap. Remove
front and rear engine lifting hooks. Remove upper radiator hose, by-pass hose and bracket.
4. Remove bolts retaining rocker arm shaft. Remove rocker arm assemblies. Remove cylinder head bolts. Remove head and gasket.
Inspection (1.3L)
1. Thoroughly clean and check gasket mating surface of cylinder head and block. Check cylinder for cracks, nicks, burrs or damage. Using
a straightedge and feeler gauge, check warpage over entire gasket area. Ensure cylinder head and/or block warpage does not
exceed .006" (.15 mm).
2. If warpage exceeds .006" (.15 mm), machine cylinder head and/or block gasket surface. Maximum machining allowed is .008" (.20 mm).
If more machining is required, replace block and/or cylinder head.
Installation (1.3L)
1. Place new head gasket properly on block. Carefully place cylinder head in position on block. Install head bolts. Tighten bolts in
sequence and in 2 steps. See Fig. 1
.
2. While tightening rocker arm shaft, slide shaft springs away from retaining bolt to prevent pinching springs. Tighten rocker arm shaft bolts
in sequence and to specification. See Fig. 5
. To complete installation, reverse removal procedure. Tighten all bolts/nuts to
specification. Fill all fluids to proper levels. NOTE:T urbocharger-to-exhaust m anifold m ounting nuts are of special quality. Ensure correct nuts are
used.
NOTE:Ensure one brass washer is positioned on each side of oil line fitting.
NOTE:Feed O2 sensor wire through upper heat shield. Install wire retainer under LH bolt.
NOTE:If turbocharger was replaced: Disconnect ignition coil, crank engine for 20 seconds, connect ignition
coil, start engine and run at idle for 30 seconds and check for leaks.
NOTE:If original tim ing belt is being reused, m ark direction of rotation for installation reference.
Page 4 of 19 MITCHELL 1 ARTICLE - ENGINE OVERHAUL 1991-92 FORD MOTOR CO. ENGINES 1.3L & 1.6L 4-Cylinder
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Remove timing belt covers, See TIMING BELT COVER procedure to remove timing belt from this engine.
Installation (1.6L)
1. Ensure timing belt and sprockets are clean and not worn or damaged. Ensure timing marks are properly positioned on camshafts and
crankshaft. Intake cam should have letter "I" aligned with arrow on belt cover. Exhaust cam should have letter "E" aligned with arrow on
belt cover. Crankshaft key should align with arrow. See Fig. 4
.
2. Tighten tension pulley with tension spring fully extended. Install timing belt. Keep tension on opposite side of tensioner as tight as
possible. Ensure rotation mark on belt is correct.
3. Turn crankshaft 2 full turns. Check alignment of timing marks. If any mark is not aligned, remove timing belt and reset timing. Lo o se n
tension pulley retaining bolt allowing tension spring to tighten belt. Tighten tension pulley to specification and rotate engine 2 full
turns. Verify timing mark alignment.
4. Measure timing belt tension between camshaft pulleys. Belt deflection should be 0.33-0.45" (8.5-11.5 mm). If incorrect, loosen tension
pulley and repeat procedure. If correct tension cannot be achieved, replace tension spring.
5. Install lower, center and upper timing belt covers, and tighten bolts to specification. See TORQUE SPECIFICATIONS
table at end of
article. Install RH engine mount. Lower engine. Tighten retaining nuts to specification. Install crankshaft pulley, damper and baffle.
Tighten baffle and damper screws and pulley retaining bolts to specification. Install water pump pulley and tighten retaining bolts to
specification.
6. Install alternator and power steering belts. Install oil dipstick. Raise vehicle and install splash guard and RF wheel and tire assembly.
Lower vehicle, install spark plugs and start engine. Inspect for leaks and check operation.

Fig. 4: Aligning Camshaft & Crankshaft Timing Marks (1.6L)

Courtesy of FORD MOTOR CO.
FRONT COVER & OIL SEAL
Removal & Installation
Front cover is the housing for the oil pump. See OIL PUMP under ENGINE OILING.
CAMSHAFT
Removal (1.3L)
Remove cylinder head. Remove rocker arm assemblies if not previously removed. Carefully remove camshaft thrust plate. Remove camsh aft
Page 7 of 19 MITCHELL 1 ARTICLE - ENGINE OVERHAUL 1991-92 FORD MOTOR CO. ENGINES 1.3L & 1.6L 4-Cylinder
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bearing oil seal. To complete installation, reverse removal procedure.
WATER PUMP
Removal & Installation (1.3L)
Remove timing belt. Drain cooling system. Remove lower radiator hose and heater return hose from water pump. Remove water pump
retaining bolts and water pump. Clean gasket mounting surface and replace gasket. To install, reverse removal procedure.
Removal (1.6L)
1. Remove timing belt. See TIMING BELT . Drain cooling system. Remove timing belt tensioner and idler pulleys. Remove oil dipstick
bracket retaining bolt.
2. Remove power steering pump from retaining bracket, leaving hoses attached. Remove power steering bracket and position power
steering pump to one side. Remove water pump outlet. Remove water pump retaining bolts and water pump.
Installation (1.6L)
1. Clean all gasket surfaces. Transfer rubber belt cover seal to new water pump (if required). Position water pump with new gasket and
install retaining bolts. Install pump outlet with new gasket and "O" ring. See TORQUE SPECIFICATIONS
table at end of article.
2. Install oil dipstick retaining bolt. Install timing belt tensioner and idler pulleys. Install power steering pump bracket. Install power
steering pump. Tighten all bolts and nuts to specification. See TORQUE SPECIFICATIONS
table at end of article.
3. Install timing belt. Fill cooling system. Start engine and check for leaks and proper system function.
OIL PAN
Removal (1.3L)
Disconnect battery ground cable. Raise vehicle and drain engine oil. Remove flywheel housing dust cover. Remove oil pan retaining bolts,
nuts and stiffeners. Rotate crankshaft while removing oil pan. Remove baffle plate from oil pan. Clean gasket mating surfaces thoroughly.
Installation (1.3L)
Ensure gasket surfaces are clean. Apply oil resistant sealer to front and rear engine covers and across joint line of cylinder block.
Removal (1.6L)
1. Raise vehicle and drain engine oil. Remove frame brace retaining bolt. Loosen RH "A" arm front bolt, and pivot brace downward.
Disconnect front exhaust pipe from exhaust manifold (or turbocharger). Remove exhaust pipe bracket retaining bolts. Loosen rubber
exhaust hangers at catalytic converter.
2. Allow exhaust to hang supported by mechanic's wire. Disconnect turbocharger oil return hose (if equipped). Remove oil pan retaining
bolts. Carefully pry oil pan loose from cylinder block.
Installation (1.6L)
1. Clean pan and block gasket surfaces. Apply Gasket Sealant (E3AZ-19562-A) to new front and rear pan seals. Install seals to cylinder
block. Apply Gasket Sealant (E3AZ-19562-A) to oil pan gasket surface. See Fig. 8
. Install oil pan and tighten pan retaining bolts to
specification. See TORQUE SPECIFICATIONS
table at end of article.
2. Connect turbocharger oil return hose (if equipped). Install rubber exhaust hanger to brackets. Install new gasket and connect fro n t
exhaust pipe to exhaust manifold (or turbocharger). Install front exhaust pipe bracket. Tighten nuts and bolts to specification.
3. Pivot frame brace into position. Tighten retaining bolt to crossmember and RH "A" arm front retaining bolt to specification. Lower
vehicle, fill with oil and start engine. Check for oil leaks and system operation. NOTE:Raise engine slightly with floor jack, if required, to gain clearance for water pum p rem oval.
CAUT ION: DO NOT force a pry tool between cylinder block and oil pan.
Page 11 of 19 MITCHELL 1 ARTICLE - ENGINE OVERHAUL 1991-92 FORD MOTOR CO. ENGINES 1.3L & 1.6L 4-Cylinder
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Crankshaft Pulley Bolts10-13 (12-17)
Crankshaft Sprocket Bolt80-87 (108-118)
Power Steering Adjuster Nut27-38 (37-52)
Timing Belt Tensioner Adjuster Bolt14-19 (19-26)
Water Pump Pulley Bolts36-45 (49-61)
INCH Lbs. (N.m)
Camshaft Cover71-97 (8-11)
Timing Belt Cover Bolt71-97 (8-11)
Valve Cover Bolt44-79 (5-9)
Copyr ight 2009 Mitchell Repair Information Company, LLC. All Rights Reserved.
Article GUID: A00155957
Page 3 of 3 MITCHELL 1 ARTICLE - FORD 1.3L 4-Cylinder
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Removal
Drain radiator and remove negative battery cable. Disconnect throttle cable. Remove air duct from throttle body. Disconnect throttle position
sensor/switch connector. Mark all coolant and vacuum hoses for reassembly reference and remove from throttle body. See Fig. 4
. Remove
intake plenum bolts and remove intake plenum and gasket.
Installation
To install, reverse removal procedure. Use NEW intake plenum-to-intake manifold gasket. Tighten bolts to specification, see TORQUE
SPECIFICATIONS at end of article.
OXYGEN (O2) SENSOR
Removal & Installation
Disconnect negative battery cable. Disconnect wire harness connector, and remove oxygen sensor. If exhaust sensor is difficult to remove, use
rust penetrant to avoid possible damage to exhaust threads. If new sensor is not pre-coated with anti-seize, apply anti-seize compound to
sensor threads. DO NOT remove anti-seize from sensor. To install, tighten sensor and attach wire harness connector.
THROTTLE BODY
Removal & Installation
Drain radiator and remove negative battery cable. Remove resonance chamber. Disconnect throttle cable. Remove air duct. Mark all coolant
and vacuum hoses for reassembly reference and remove from throttle body. Disconnect throttle position sensor/switch connector. Remove
throttle body nuts and bolts. Remove throttle body and gasket. To install, reverse removal procedure using NEW throttle body-to-intake
plenum gasket.
THROTTLE POSITION SENSOR/SWITCH
Removal & Installation
Disconnect negative battery cable. Disconnect throttle position sensor/switch connector. Remove attaching bolts. Remove sensor/switch from
throttle body. To install, reverse removal procedure.
TURBOCHARGER
Removal
1. Drain radiator and remove negative battery cable. Remove throttle body air intake tube. Disconnect intercooler hose from turbocharger
assembly. Disconnect O2 sensor. Remove lower heat shield retaining bolts and lower heat shield from turbocharger. Remove upper heat
shield retaining bolts and upper heat shield from exhaust manifold.
2. Slide O2 sensor wire and guide through upper heat shield. Remove side heat shield retaining bolts from turbocharger, and remove sid e
heat shield. Remove power steering belt. Remove power steering pump through bolt and adjuster nuts and bolts. Disconnect lower
radiator hose from water pump.
3. Pull pump from bracket, and position pump to access mounting bracket retaining nut and bolts. Remove mounting bracket-to-engine nut
and bolts and remove bracket. Remove air cleaner duct retaining screws. Loosen clamp at turbocharger and move duct tube out of way.
Disconnect coolant supply hose at turbocharger.
4. Remove bolt and sealing washers attaching oil supply line at engine block. Raise vehicle on hoist. Remove nuts and washers from
exhaust pipe flange. Remove bolts attaching exhaust hanger to engine block. Slide rubber exhaust hangers from catalytic converter. Pull
exhaust pipe downward and to left side of vehicle. Disconnect oil return hose from turbocharger. Disconnect coolant return hose fro m
turbocharger.
5. Remove turbocharger support bracket retaining bolts. Remove coolant by-pass tube outlet-to-water pump bolts. Lower vehicle. Loosen
retaining clamp bolt on coolant by-pass tube at rear of cylinder head. Remove 11 retaining nuts from exhaust manifold. Position coolant
by-pass tube out of way after pulling bracket from exhaust stud.
6. Remove exhaust manifold by pulling off studs and moving assembly towards right side of engine compartment, clearing cooling fan.
With assembly removed from vehicle, remove turbocharger-to-exhaust manifold nuts. Separate assembly and discard gasket.
Installation
1. Install NEW gasket on exhaust manifold and install turbocharger onto studs. Install turbocharger-to-exhaust manifold nuts. Remo ve o il
supply line from turbocharger. Install NEW exhaust gasket on cylinder head. Install turbocharger and exhaust manifold assembly onto
studs. Install coolant by-pass tube bracket onto exhaust stud. Install 11 retaining nuts onto exhaust manifold.
2. Securely tighten heater tube clamp bolt. Raise vehicle. Install coolant by-pass tube outlet-to-water pump bolts. Install turbocharger
support bracket retaining bolts. Connect coolant return hose to turbocharger. Connect oil return hose to turbocharger. Install exhaust
pipe onto turbocharger, and hand tighten nuts and washers. Install bolts attaching exhaust hanger to engine block.
3. Slide rubber exhaust hangers onto catalytic converter. Tighten exhaust pipe nuts and washers. Lower vehicle. Install bolt and sealing
washers attaching oil supply line at engine block. Install oil supply line onto turbocharger. To complete installation, reverse removal
procedure. Tighten bolts and nuts to specification, see TORQUE SPECIFICATIONS
at end of article. NOTE:T o prevent dust and dirt from entering intake m anifold ports, cover ports with clean cloth after
rem oving intake plenum .
WARNING:DO NOT rem ove oxygen sensor when engine is hot.
NOTE:Clean throttle body exterior before rem oval.
CAUT ION: Before installing turbocharger, put .8 oz. (25 m l) engine oil into turbocharger oil inlet.
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VANE AIRFLOW (VAF) METER
Removal
1. Disconnect negative battery cable. On Capri, disconnect primary and secondary wires from coil. On Festiva, disconnect VAF wire
harness connector. Remove air duct.
2. On Capri, remove retaining bolt and ground wire from air cleaner cover. Remove air cleaner cover bolts and air cleaner cover. From
inside of air cleaner cover, remove VAF meter retaining nuts. On Festiva, remove attaching bolt and 4 nuts. Remove vane airflow met er.
Installation
To install, reverse removal procedure. Position new gasket over VAF mounting studs. Tighten bolts and nuts to specification, see TORQUE
SPECIFICATIONS at end of article.
TORQUE SPECIFICATIONS
TORQUE SPECIFICATIONS NOTE:For all on-vehicle adjustm ents not covered in this article, see ADJUST MENT S article in the ENGINE
PERFORMANCE Section.
ApplicationFt. Lbs. (N.m)
Coolant By-Pass Tube Outlet-To-Water Pump Bolts14-19 (19-26)
Distributor Mounting Bolts14-19 (19-26)
Exhaust Manifold Retaining Nuts29-42 (39-57)
Exhaust Pipe Nuts18-25 (24-34)
Fuel Line-To-Fuel Filter Bolt18-25 (24-34)
Fuel Pressure Regulator Nut(1)
Fuel Rail Retaining Bolt14-19 (19-26)
Heat Shield Bolts14-19 (19-26)
Intake Plenum Bolts/Nuts11-16 (15-22)
Oil Supply Line-To-Turbocharger Bolt12-17 (16-23)
Oxygen Sensor(1)
Power Steering Pump Bracket-To-Engine Bolts/Nut35-48 (47-65)
Throttle Body Bolt/Nuts12-17 (16-23)
Turbocharger Support Bracket Bolts32-45 (43-61)
Turbocharger-To-Exhaust Manifold Nuts20-25 (27-34)
INCH Lbs. (N.m)
Barometric Pressure (BP) Sensor Nut54-84 (6-9)
MAP Sensor Nuts54-84 (6-9)
Oil Supply Line-To-Engine Block Bolt104-156 (12-18)
Vane Airflow Meter Nuts110-152 (12-18)
(1)Information not available from manufacturer.
Copyr ight 2009 Mitchell Repair Information Company, LLC. All Rights Reserved.
Article GUID: A00022705
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POWER STEERING PRESSURE SWITCH
1. Start engine and run it at idle. Remove connector from switch. Connect ohmmeter to switch terminals. Turn steering wheel from side to
side while observing ohmmeter.
2. Replace power steering switch if continuity does not exist with front wheels turned, or if continuity exists with wheels straight ahead.
THROTTLE POSITION SENSOR (1.6L)
Unplug connector from sensor. Connect ohmmeter to sensor terminals TP and SIGRTN (Orange and Blue/Yellow wires on mating connector).
Measure resistance at each throttle opening specified in THROTTLE POSITION SENSOR RESISTANCE
. Replace sensor if resistance is
not within specification.
THROTTLE POSITION SENSOR RESISTANCE
THROTTLE POSITION SWITCH (1.3L)
1. Ensure idle speed and ignition timing are adjusted to specification. Stop engine. Disconnect negative battery cable.
2. Unplug TPS connector at throttle body. Insert appropriate feeler gauge between throttle stop screw and stop lever. Check for continuity
between specified terminals on TPS connector. See ON-VEHICLE ADJUSTMENTS article and TPS CONTINUITY table.
TPS CONTINUITY
VANE AIRFLOW (VAF) METER
1. Check all wiring, harnesses, connectors and components for evidence of damage, overheating, shorting or looseness. If any defect exists,
repair as necessary.
2. Inspect vane airflow meter for damage and ensure measuring plate moves smoothly. Install BOB. Turn ignition on. Measure voltage
between BOB test pins VAF and ground on 1.3L, or between VAF and SIGRTN on 1.6L. Voltage measurements must be as specified in
VANE AIRFLOW METER VOLTAG
.
VANE AIRFLOW METER VOLTAGE
VANE AIR TEMPERATURE (VAT) SENSOR
1. Unplug connector from VAF meter. On 1.3L, connect ohmmeter to terminals VAT and ground (Green/Black and Black wires on mating
connector). On 1.6L, connect ohmmeter to VAF meter terminals VAT and SIGRTN (Brown and Blue/Yellow wires on mating
connector).
2. Measure intake air temperature. Measure resistance between specified terminals. See VANE AIR TEMPERATURE RESISTANCE
.
Replace VAF if resistance is not as specified.
Throttle Opening(1) Ohms
1/8989
1/41104
3/81278
1/21462
5/81480
3/41459
7/81144
Fully Open1072
(1)Resistance may vary by plus or minus 15 percent.
CAUT ION: DO NOT tam per with throttle stop screw at throttle lever. Doing so m ay result in dam age to the
throttle body.
Test Condition (1) Cont. Between IDL-TLCont. Between PSW-TL
.02" (.5 mm)YesNo
.03" (.7 mm)NoNo
Wide Open ThrottleNoYes
(1)Insert specified feeler gauge between throttle adjustment screw and stop lever.
Door Opening(1) Volts: 1.3L(1) Volts: 1.6L
Fully Closed.5-1.5(2) *
1/8.593.24
1/41.195.60
3/81.785.62
1/22.385.83
5/82.976.02
3/43.566.57
7/84.167.48
Fully Open4.5-5.07.87
(1)Voltage may vary by plus or minus 15 percent.
(2)Voltage not specified.
Page 3 of 7 MITCHELL 1 ARTICLE - I - SYSTEM/COMPONENT TESTS 1991 ENGINE PERFORMANCE Ford Motor Co. - Ford/Merc
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CLUTCH ENGAGE SWITCH (CES)
This switch is located on the manual transaxle and informs the ECA of transmission operating conditions. The ECA uses this data fo r id l e
speed control and canister purge valve operation.
CRANKSHAFT POSITION SENSOR (CPS) (FESTIVA)
This sensor is located in the distributor and sends engine RPM and crankshaft position data to the ECA. The ECA uses this data in calculating
fuel metering, ignition timing, idle speed control and canister purge valve operation.
CYLINDER IDENTIFICATION SENSOR (CID) (CAPRI)
This sensor is located in the distributor and provides crankshaft position data to the ECA. The ECA uses this data in calculating fuel metering
and ignition timing.
ELECTRICAL LOAD SWITCHES
Blower control, cooling fan, rear window defroster, air conditioning and headlight switches all send signals to the ECA. The ECA uses these
signals for idle speed control.
ENGINE COOLANT TEMPERATURE (ECT) SENSOR
This sensor is located in the intake manifold and sends coolant temperature data to the ECA. The ECA uses this data in calculating fuel
metering, idle speed control and canister purge valve operation.
EXHAUST GAS OXYGEN (EGO) SENSOR
This sensor is located in the exhaust manifold and senses oxygen concentration in the exhaust gas. The ECA uses this data in calculating fuel
metering, idle speed control and canister purge valve operation.
NEUTRAL SAFETY SWITCH (A/T)
This switch is located on the automatic transaxle and sends a signal to the ECA whenever the transaxle is in Neutral or Park ranges. The ECA
uses this signal in calculating fuel metering, idle speed control and canister purge valve operation.
POWER STEERING PRESSURE SWITCH (PSPS)
This switch is located on the power steering pump and sends data about power steering operation to the ECA. The ECA uses this data for idle
speed control.
THROTTLE POSITION SENSOR (TP)
This device is located on the throttle body and contains 2 switches. The Wide Open Throttle (WOT) Switch sends a signal to the ECA when
throttle valve opening is more than 70 degrees. The ECA uses this signal in calculating fuel metering.
The Idle Switch (IDL) sends a signal to the ECA when throttle valve opening is less than 1.5 degrees. The ECA uses this signal for idle speed
control and canister purge valve operation.
VANE AIRFLOW (VAF) METER
This sensor is located in the air cleaner housing and sends intake airflow data to the ECA. The ECA uses this data in calculating fuel metering.
VANE AIR TEMPERATURE (VAT) SENSOR
This sensor is located inside the vane airflow sensor and senses intake air temperature. The ECA uses this data in calculating fu el met erin g,
idle speed control and canister purge valve operation.
CEC OUTPUT SIGNALS
CANISTER PURGE (CANP) SOLENOID
See EMISSION SYSTEMS.
CHECK ENGINE LIGHT
See SELF-DIAGNOSTIC SYSTEM.
FUEL INJECTORS
See FUEL CONTROL.
IDLE SPEED CONTROL BY-PASS AIR (ISC-BPA) VALVE
See IDLE SPEED. NOTE:Vehicles are equipped with different com binations of com puter-controlled com ponents. Not all
com ponents listed below are used on every vehicle. For theory and operation of each output
com ponent, refer to indicated system .
Page 2 of 6 MITCHELL 1 ARTICLE - E - THEORY/OPERATION 1991 ENGINE PERFORMANCE Ford/Mercury Theory & Operation
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Profile Ignition Pick-up
PNP
Park Neutral Position Switch
P/N
Park/Neutral
PRNDL
Park Reverse Neutral Drive Low
PROM
Programmable Read-Only Memory
psi
Pounds Per Square Inch
P/S
Power Steering
PSPS
Power Steering Pressure Switch
PTC
Positive Temperature Coefficient
PTO
Power Take-Off
Pts.
Pints
Pwr.
Power
"Q"
Qts.
Quarts
"R"
RABS
Rear Anti-Lock Brake System
RECIRC
Recirculation
RH
Right Hand
RPM
Revolutions Per Minute
RWAL
Rear Wheel Anti-Lock Brake
RWD
Rear Wheel Drive
"S"
Page 12 of 15 MITCHELL 1 ARTICLE - GENERAL INFORMATION Commonly Used Abbreviations
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Throttle Actuator Module
TAD
Thermactor Air Diverter
TBC
Body Control Module
TBI
Throttle Body Injection
TCC
Torque Converter Clutch
TDC
Top Dead Center
Temp.
Temperature
TFI
Thick Film Ignition
THERMAC
Thermostatic Air Cleaner
TPM
Tire Pressure Monitor
TPMS
Tire Pressure Monitor System
TPS
Throttle Position Sensor/Switch
TS
Temperature Sensor
TV
Thermovalve
TWC
Three-Way Catalyst
"V"
V
Valve
Vac.
Vacuum
VAF
Vane Airflow
VAPS
Variable Assist Power Steering
VCC
Viscous Converter Clutch
Page 14 of 15 MITCHELL 1 ARTICLE - GENERAL INFORMATION Commonly Used Abbreviations
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