check engine OPEL FRONTERA 1998 Workshop Manual

6E–310
ENGINE DRIVEABILITY AND EMISSIONS
Pedal Stroke Adjustment Procedure
1. Loosen the jam nut and rotate the kick-down switch
counterclockwise.
TS24039
2. Fully depress the pedal and hold it by hand. Rotate
the switch clockwise until the switch clicks.
3. Rotate the switch 1/2 turn further and lock it in this
position by tightening the jam nut.
TS24040
4. Step on the accelerator pedal and make sure there is
a clicking sound at the full-stroke position.
Fuel Filter Cap
General Description
The fuel filler cap includes a vacuum valve and a pressure
valve.If high vacuum or high pressure occurs in the fuel tank,
each valve works to adjust the pressure in order to
prevent damage to the tank at the EGR valve.
TS23767
Inspection Procedure
NOTE: Replace the fuel filler cap with the same type of
filler cap that was originally installed on the vehicle.
Check the seal ring in the filler cap for any abnormality
and for seal condition.
Replace the filler cap if any abnormality is found.
Fuel Filter
Removal Procedure
1. Disconnect the negative battery cable.
2. Remove the fuel filler cap.
041RW005

6E–314
ENGINE DRIVEABILITY AND EMISSIONS
3. Connect the wiring connector to the fuel gauge unit.
TS23771
4. Fill the fuel tank with fuel.
Tighten the fuel filler cap.
Check for leaks at the fuel gauge unit gasket.
5. Connect the negative battery cable.
Fuel Injectors
Removal Procedure
NOTE: If the fuel injectors are leaking, the engine oil may
be contaminated with fuel. Check the oil for signs of
contamination and change the oil and the filter if
necessary.
NOTE: Use care in removing the fuel injectors in order to
prevent damage to the fuel injector electrical connector
pins or the fuel injector nozzles. The fuel injector is an
electrical component and should not be immersed in any
type of cleaner as this may damage the fuel injector.
IMPORTANT:Fuel injectors are serviced as a complete
assembly only.
1. Disconnect the negative battery cable.
2. Remove the upper intake manifold. Refer to
Common Chamber in Engine Mechanical..
3. Remove the fuel rail. Refer to
Fuel Rail.
014RW164
4. Remove the injector retainer clip.
055RW009
5. Remove the fuel injector assembly.
6. Remove the O-ring from the fuel injector.
7. Remove the O-ring backup from the fuel injector .
Inspection Procedure
1. Inspect the O-rings for cracks or leaks.
2. Replace worn or damaged O-rings.
3. Lubricate the new O-rings with engine oil before
installation.

6E–325 ENGINE DRIVEABILITY AND EMISSIONS
Spark Plug Gap Check
Check the gap of all spark plugs before installation.
Use a round wire feeler gauge to ensure an accurate
check.
Plugs installed with the wrong gap can cause poor
engine performance and excessive emissions.
Installation Procedure
NOTE: The plug must thread smoothly into the cylinder
head and be fully seated. Use a thread chaser if
necessary to clean the threads in the cylinder head.
Cross-threading or failure to fully seat the spark plug can
cause plug overheating, exhaust blow-by gas, or thread
damage. Do not overtighten the spark plugs. Over
tightening can cause aluminum threads to strip.
1. Install the spark plug in the engine. Use the
appropriate spark plug socket.
Tighten
Tighten the spark plug to 18 Nꞏm (13 lb ft.).
2. Install the ignition coil and spark plug boot over the
spark plug.
014RW108
3. Secure the ignition coil to the rocker cover with two
screws.
014RW091
4. Connect the electrical connector at the ignition coil.
5. Connect the negative battery cable.
Catalytic Converter
Removal and Installation Procedure
Refer to Engine Exhaust in Engine.
Air Conditioning Relay
Removal Procedure
1. Remove the fuse and relay box cover from under the
hood.
2. Consult the diagram on the cover to determine which
is the correct relay.
3. Insert a small screwdriver into the catch slot on the
forward side of the fuel pump relay.
The screwdriver blade will release the catch inside.
T321092

6E–330
ENGINE DRIVEABILITY AND EMISSIONS
Wiring and Connectors
Wiring Harness Service
The control module harness electrically connects the
control module to the various solenoids, switches and
sensors in the vehicle engine compartment and
passenger compartment.
Replace wire harnesses with the proper part number
replacement.
Because of the low amperage and voltage levels utilized
in powertrain control systems, it is essential that all wiring
in environmentally exposed areas be repaired with crimp
and seal splice sleeves.
The following wire harness repair information is intended
as a general guideline only. Refer to
Chassis Electrical f o r
all wire harness repair procedures.
Connectors and Terminals
Use care when probing a connector and when replacing
terminals. It is possible to short between opposite
terminals. Damage to components could result. Always
use jumper wires between connectors for circuit
checking. NEVER probe through Weather-Pack seals.
Use an appropriate connector test adapter kit which
contains an assortment of flexible connectors used to
probe terminals during diagnosis. Use an appropriate
fuse remover and test tool for removing a fuse and to
adapt the fuse holder to a meter for diagnosis.
Open circuits are often difficult to locate by sight because
oxidation or terminal misalignment are hidden by the
connectors. Merely wiggling a connector on a sensor, or
in the wiring harness, may temporarily correct the open
circuit. Intermittent problems may also be caused by
oxidized or loose connections.
Be certain of the type of connector/terminal before
making any connector or terminal repair. Weather-Pack
and Com-Pack III terminals look similar, but are serviced
differently.
PCM Connectors and Terminals
Removal Procedure
1. Remove the connector terminal retainer.
2. Push the wire connected to the affected terminal
through the connector face so that the terminal is
exposed.
3. Service the terminal as necessary.
Installation Procedure
1. Bend the tab on the connector to allow the terminal to
be pulled into position within the connector.
2. Pull carefully on the wire to install the connector
terminal retainer.
Wire Harness Repair: Twisted
Shielded Cable
Removal Procedure
1. Remove the outer jacket.
2. Unwrap the aluminum/mylar tape. Do not remove the
mylar.
047
3. Untwist the conductors.
4. Strip the insulation as necessary.
048

6E–344
ENGINE DRIVEABILITY AND EMISSIONS
0006
Run Mode
The run mode has the following two conditions:
Open loop
Closed loop
When the engine is first started the system is in “open
loop” operation. In “open loop,” the PCM ignores the
signal from the heated oxygen sensor (HO2S). It
calculates the air/fuel ratio based on inputs from the TP,
ECT, and MAF sensors.
The system remains in “open loop” until the following
conditions are met:
The HO2S has a varying voltage output showing that
it is hot enough to operate properly (this depends on
temperature).
The ECT has reached a specified temperature.
A specific amount of time has elapsed since starting
the engine.
Engine speed has been greater than a specified RPM
since start-up.
The specific values for the above conditions vary with
different engines and are stored in the programmable
read only memory (PROM). When these conditions are
met, the system enters “closed loop” operation. In
“closed loop,” the PCM calculates the air/fuel ratio
(injector on-time) based on the signal from the HO2S.
This allows the air/fuel ratio to stay very close to 14.7:1.
Starting Mode
When the ignition is first turned “ON,” the PCM energizes
the fuel pump relay for two seconds to allow the fuel pump
to build up pressure. The PCM then checks the engine
coolant temperature (ECT) sensor and the throttle
position (TP) sensor to determine the proper air/fuel ratio
for starting.
The PCM controls the amount of fuel delivered in the
starting mode by adjusting how long the fuel injectors are
energized by pulsing the injectors for very short times.
Throttle Body Unit
The throttle body has a throttle plate to control the amount
of air delivered to the engine. The TP sensor and IAC
valve are also mounted on the throttle body. Vacuum
ports located behind the throttle plate provide the vacuum
signals needed by various components.
Engine coolant is directed through a coolant cavity in the
throttle body to warm the throttle valve and to prevent
icing.
0019
General Description (Electronic
Ignition System)
Camshaft Position (CMP) Sensor
As the camshaft sprocket turns, a magnet in the sprocket
activates the Hall-effect switch in the CMP sensor. When
the Hall-effect switch is activated, it grounds the signal
line to the PCM, pulling the camshaft position sensor
signal circuit’s applied voltage low. This is a CMP signal.
The CMP signals is created as piston #1 is approximately
25
after top dead counter on the power stroke. If the
correct CMP signal is not received by the PCM, DTC
P0341 will be set.

6E–348
ENGINE DRIVEABILITY AND EMISSIONS
oil to enter the cylinder, particularly if the deposits are
heavier on the side of the spark plug facing the intake
valve.
TS23995
Excessive gap means that the air space between the
center and the side electrodes at the bottom of the spark
plug is too wide for consistent firing. This may be due to
improper gap adjustment or to excessive wear of the
electrode during use. A check of the gap size and
comparison to the gap specified for the vehicle in
Maintenance and Lubrication will tell if the gap is too wide.
A spark plug gap that is too small may cause an unstable
idle condition. Excessive gap wear can be an indication
of continuous operation at high speeds or with engine
loads, causing the spark to run too hot. Another possible
cause is an excessively lean fuel mixture.
TS23992
Low or high spark plug installation torque or improper
seating can result in the spark plug running too hot and
can cause excessive center electrode wear. The plug
and the cylinder head seats must be in good contact for
proper heat transfer and spark plug cooling. Dirty or
damaged threads in the head or on the spark plug cankeep it from seating even though the proper torque is
applied. Once spark plugs are properly seated, tighten
them to the torque shown in the Specifications Table. Low
torque may result in poor contact of the seats due to a
loose spark plug. Overtightening may cause the spark
plug shell to be stretched and will result in poor contact
between the seats. In extreme cases, exhaust blow-by
and damage beyond simple gap wear may occur.
Cracked or broken insulators may be the result of
improper installation, damage during spark plug
re-gapping, or heat shock to the insulator material. Upper
insulators can be broken when a poorly fitting tool is used
during installation or removal, when the spark plug is hit
from the outside, or is dropped on a hard surface. Cracks
in the upper insulator may be inside the shell and not
visible. Also, the breakage may not cause problems until
oil or moisture penetrates the crack later.
TS23994
A broken or cracked lower insulator tip (around the center
electrode) may result from damage during re-gapping or
from “heat shock” (spark plug suddenly operating too
hot).
TS23993

6F–3 ENGINE EXHAUST
For Isuzu General Motors (IGM)
150RW058
When inspecting or replacing exhaust system
components, make sure there is adequate clearance
from all points on the underbody to prevent overheating
the floor pan and possible damage to the passenger
compartment insulation and trim materials.
Check complete exhaust system and nearby body areas
and rear compartment lid for broken, damaged, missing
or mispositioned parts, open seams, holes, loose
connections or other deterioration which could permit
exhaust fumes to seep into the rear compartment or
passenger compartment. Dust or water in the rear
compartment may be an indication of a problem in one of
these areas. Any faulty areas should be corrected
immediately.
Hangers
Various types of hangers are used to support exhaust
system(s). These include conventional rubber straps,
rubber rings, and rubber blocks.
The installation of exhaust system supports is very
important, as improperly installed supports can cause
annoying vibrations which can be difficult to diagnose.
Three Way Catalytic Converter
The three way catalytic converter is an emission control
device added to the exhaust system to reduce pollutants
from the exhaust gas stream.
CAUTION: The catalytic converter requires the use
of unleaded fuel only.
Periodic maintenance of the exhaust system is not
required. If the vehicle is raised for other service, it is
advisable to check the condition of the complete exhaust
system.
A dual bed monolith catalytic converter is used in
combination with three way catalytic converter.
Catalytic Types:
Three way (Reduction/Oxidation) catalyst
The catalyst coating on the three way (reduction)
converter contains platinum and rhodium which lowers
the levels of nitrous oxide (NOx) as well as hydrocarbons
(HC) and carbon monoxide (Co).
Gasket
The gasket must be replaced whenever a new exhaust
pipe, muffler or catalytic converter is installed.

6G–4
ENGINE LUBRICATION
11. Remove drive gear.
12. Remove oil seal.
13. Remove O-ring.
Inspection and Repair
CAUTION: Make necessary correction or parts
replacement if wear, damage or any other abnormal
conditions are found during inspection.
Relief Valve (8)
Check to see that the relief valve slides freely.
The oil pump must be replaced if the relief valve does
not slide freely.
Replace the spring and/or the oil pump assembly (5) if
the spring is damaged or badly worn.
051RS002
Body (14) and Gears (10, 11)
The pump assembly must be replaced if one or more of
the conditions below is discovered during inspection.
Badly worn or damaged driven gear (10).
Badly worn drive gear (11) driving face.
Badly scratched or scored body sliding face (14) or
driven gear (10).
Badly worn or damaged gear teeth.
Measure the clearance between the body and the driven
gear with a feeler gauge.
Standard : 0.10 mm–0.18 mm
(0.0039 in.–0.0070 in)
Limit : 0.20mm (0.0079 in)
051RS004
Measure the clearance between the drive gear and
driven gear with a feeler gauge.
Standard : 0.11 mm–0.24 mm
(0.0043 in–0.0094 in)
Limit : 0.35mm (0.0138 in)
051RS003
Measure the side clearance with a precision straight
edge and a feeler gauge.
Clearance
Standard : 0.03 mm–0.09 mm
(0.0011 in–0.0035 in)
Limit : 0.15mm (0.0059 in)

6G–5 ENGINE LUBRICATION
051RS005
Oil Strainer
Check the oil strainer for cracking and scoring. If cracking
and scoring are found, the oil strainer must be replaced.
051RS006
Reassembly
1. Install drive gear (11).
2. Install driven gear (10).
3. Install oil pump cover (9) and first, loosely tighten all of
the attaching screws. Next, tighten the attaching
screws to the specified torque.
Torque : 10 Nꞏm (1.0 Kgꞏm/89 lb in)
After installation, check that the gear rotates
smoothly.
4. Install relief valve (8) and apply engine oil to the relief
valve and spring (7).
5. Install spring (7).6. Install the plug (6).
Torque : 8 Nꞏm (0.8 Kgꞏm/69 lb in)
051RS007
7. Install oil pump assembly (5).
Carefully remove any oil from the cylinder body and
the pump. Apply sealant (TB–1207B or equivalent)
to the pump fitting face as shown in illustration. Take
care that sealant is not applied to oil port surfaces.
The oil pump assembly must be installed within 5
minutes after sealant application before the sealant
hardens.
CAUTION: Do not apply an excessive amount of
sealant to the contact surface. Applying too much
sealant will overflow the contact surfaces. This
could cause serious damage to the engine.
Attach oil pump assembly to cylinder body.
Tighten the oil pump fixing bolts.
Torque : 25 Nꞏm (2.5 Kgꞏm/18 lbꞏft)
051RW002

6H–2
ENGINE SPEED CONTROL SYSTEM
Accelerator Pedal Control Cable
Removal
1. Loosen the adjusting nut(5) on the cable bracket
mounted on the common chamber.
2. Remove cable clip(3).
3. Disconnect accelerator pedal (AP) control cable(6).
(on throttle valve side)
4. Disconnect AP control cable(1). (on AP pedal(7) side)
5. Remove molding cap(2).
6. Remove AP control cable(4).
101RW001
Inspection
Check the following items, and replace the control cable if
any abnormality is found:
The control cable should move smoothly.
The control cable should not be bent or kinked.
The control cable should be free of damage and
corrosion.
Installation
1. Install AP control cable(4).
2. Install molding cap(2).
3. Connect AP control cable(1). (on AP side)
4. Connect AP control cable(6). (on throttle valve side)
5. Install cable clip(3).
6. Install adjusting nut(5).
101RW001
Adjustment
1. Loosen adjusting nut and lock nut.
2. Pull outer cable while closing fully the throttle valve.
3. Tighten adjusting nut and lock nut temporarily.
4. Loosen adjusting nut by three turns and tighten lock
nut.
Then, manually operating the throttle valve, make
sure that the valve lever returns up to the stopper
screw.
If it does not reach the stopper screw, repeat from
step 1.
035RW004
Legend
(1) Clearance
(2) Lock Nut
(3) Adjusting Nut