motor OPEL FRONTERA 1998 Workshop Manual

6A–4
ENGINE MECHANICAL
Engine Diagnosis
Hard Starting
1. Starting Motor Does Not Turn Over
Troubleshooting Procedure
Turn on headlights and starter switch.
Condition
Possible causeCorrection
Headlights go out or dim
considerably
Battery run down or under chargedRecharge or replace battery
considerablyTerminals poorly connectedClean battery posts and terminals
and connect properly
Starting motor coil circuit shortedOverhaul or replace
Starting motor defectiveOverhaul or replace
2. Ignition Trouble — Starting Motor Turns Over But Engine Does Not Start
Spark Test
Disconnect an igniton coil from any spark plug. Connect
the spark plug tester 5–8840–0607–0, start the engine,
a n d c h e c k i f a s p a r k i s g e n e r a t e d in t h e s p a r k p l u g t e s t e r.
Before starting the engine, make sure that the spark plugtester is properly grounded. To avoid electrical shock, do
not touch the part where insulation of the igniton coil is
broken while the engine is running.
Condition
Possible causeCorrection
Spark jumps across gapSpark plug defectiveClean, adjust spark gap or replace
Ignition timing incorrectRefer to Ignition System
Fuel not reaching fuel injector(s) or
engineRefer to item 3 (Trouble in fuel
system)
Valve timing incorrectAdjust
Engine lacks compressionRefer to item 4 (Engine lacks
compression)
No sparking takes placeIgnition coil disconnected or brokenConnect properly or replace
Electronic Ignition System with
moduleReplace
Poor connections in engine harnessCorrect
Powertrain Control Module cable
disconnected or defectiveCorrect or replace
3. Trouble In Fuel System
Condition
Possible causeCorrection
Starting motor turns over and spark
occurs but engine does not start
Fuel tank emptyFill
occurs but engine does not start.Water in fuel systemClean
Fuel filter cloggedReplace filter
Fuel pipe cloggedClean or replace
Fuel pump defectiveReplace
Fuel pump circuit openCorrect or replace
Evaporative Emission Control
System circuit cloggedCorrect or replace
Multiport Fuel Injection System faultyRefer to “Electronic Fuel Injection”
section

6A–53
ENGINE MECHANICAL
2. Remove camshaft bracket fixing bolt (5), camshaft
bracket (6), then camshaft exhaust (7), and intake
side (8).
3. Remove tappet with shim (11).
4. Use the 5–8840–2446–0 valve spring compressor
and 5–8840–2547–0 valve spring compressor
adapter to remove the split collar (12), valve spring
with upper seat (13) and valve (14).
014RW042
5. Remove spark plug (1).
CAUTION: Do not remove the spark plugs when the
head and plugs are hot. Clean dirt and debris from
spark plug recess areas before removal.
Clean
Cylinder head
Carefully remove all varnish, soot and carbon from the
bare metal. Do not use a motorized wire brush on any
gasket sealing surface.
Inspection and Repair
1. Cylinder head gasket and mating surfaces for leaks,
corrosion and blow–by. If the gasket has failed,
determine the cause.
– Insufficient torque on head bolts.
– Improper installation
– Loose or warped cylinder head
– Missing dowel pins
– Warped case surface
2. Cylinder head for cracks, especially between valve
seats and in the exhaust ports.3. Cylinder head deck for corrosion, sand particles in
head and porosity.
CAUTION:
Do not attempt to weld the cylinder head. Replace
it.
Do not reuse cylinder head bolts.
4. Cylinder head deck, common chamber and exhaust
manifold mating surfaces for flatness. These
surfaces may be reconditioned by milling. If the
surfaces are “out of flat” by more than specification,
the surface should be ground to within specifications.
Replace the head if it requires machining beyond the
repairable limit.
Head surface and manifold surface
Standard: 0.05 mm (0.002 in) or less
Warpage limit: 0.2 mm (0.0079 in)
Maximum Repairable limit: 0.2 mm (0.0079 in)
Head height
Standard height : 133.2 mm (5.2441 in)
Warpage limit : 0.2 mm (0.0079 in)
Maximum Repairable limit : 133.0 mm (5.2362 in)
011RW019
5. Water jacket sealing plugs seating surfaces.
Reassembly
1. Install Spark plug and tighten all the spark plugs to
specified torque.
Torque: 18 Nꞏm (1.8 Kgꞏm/13 lb ft)
2. Tighten sub gear setting bolt.
1. Use 5–8840–2443–0 gear spring lever to turn sub
gear to right direction until the M5 bolt aligns with
the hole between camshaft driven gear and sub
gear.

6D3–2STARTING AND CHARGING SYSTEM
Starting System
General Description
Cranking Circuit
The cranking system consists of a battery, starter, starter
switch, starter relay, etc. These main components are
connected.
Starter
The cranking system employs a magnetic type reduction
starter in which the motor shaft is also used as a pinion
shaft. When the starter switch is turned on, the contacts of
magnetic switch are closed, and the armature rotates. At
the same time, the plunger is attracted, and the pinion is
pushed forward by the shift lever to mesh with the ring
gear.
Then, the ring gear runs to start the engine. When the
engine starts and the starter switch is turned off, the
plunger returns, the pinion is disengaged from the ring
gear, and the armature stops rotation. When the engine
speed is higher than the pinion, the pinion idles, so that
the armature is not driven.

6E–39 ENGINE DRIVEABILITY AND EMISSIONS
The data displayed on the other Tech 2 will appear the
same, with some exceptions. Some Tech 2s will only be
able to display certain vehicle parameters as values that
are a coded representation of the true or actual value. For
more information on this system of coding, refer to
Decimal/Binary/Hexadecimal Conversions. On this
vehicle Tech 2 displays the actual values for vehicle
parameters. It will not be necessary to perform any
conversions from coded values to actual values.
On-Board Diagnostic (OBD)
On-Board Diagnostic Tests
A diagnostic test is a series of steps, the result of which is
a pass or fail reported to the diagnostic executive. When
a diagnostic test reports a pass result, the diagnostic
executive records the following data:
The diagnostic test has been completed since the last
ignition cycle.
The diagnostic test has passed during the current
ignition cycle.
The fault identified by the diagnostic test is not
currently active.
W h e n a d i a g n o s t i c t e s t r e p o r t s a fail result, the diagnostic
executive records the following data:
The diagnostic test has been completed since the last
ignition cycle.
The fault identified by the diagnostic test is currently
active.
The fault has been active during this ignition cycle.
The operating conditions at the time of the failure.
Remember, a fuel trim DTC may be triggered by a list of
vehicle faults. Make use of all information available (other
DTCs stored, rich or lean condition, etc.) when
diagnosing a fuel trim fault.
Comprehensive Component Monitor
Diagnostic Operation
Input Components:
Input components are monitored for circuit continuity and
out-of-range values. This includes rationality checking.
Rationality checking refers to indicating a fault when the
signal from a sensor does not seem reasonable, i.e.
Throttle Position (TP) sensor that indicates high throttle
position at low engine loads or MAP voltage. Input
components may include, but are not limited to the
following sensors:
Vehicle Speed Sensor (VSS)
Crankshaft Position (CKP) sensor
Knock Sensor (KS)
Throttle Position (TP) sensor
Engine Coolant Temperature (ECT) sensor
Camshaft Position (CMP) sensor
Manifold Absolute Pressure (MAP) sensor
Mass Air Flow (MAF) sensorIn addition to the circuit continuity and rationality check,
the ECT sensor is monitored for its ability to achieve a
steady state temperature to enable closed loop fuel
control.
Output Components:
Output components are diagnosed for proper response to
control module commands. Components where
functional monitoring is not feasible will be monitored for
circuit continuity and out-of-range values if applicable.
Output components to be monitored include, but are not
limited to, the following circuits:
Idle Air Control (IAC) Motor
Electronic Transmission controls
A/C relays
Cooling fan relay
VSS output
MIL control
Cruise control inhibit
Refer to PCM and Sensors in General Descriptions.
Passive and Active Diagnostic Tests
A passive test is a diagnostic test which simply monitors a
vehicle system or component. Conversely, an active test,
actually takes some sort of action when performing
diagnostic functions, often in response to a failed passive
test. For example, the EGR diagnostic active test will
force the EGR valve open during closed throttle decel
and/or force the EGR valve closed during a steady state.
Either action should result in a change in manifold
pressure.
Intrusive Diagnostic Tests
This is any on-board test run by the Diagnostic
Management System which may have an effect on
vehicle performance or emission levels.
Warm-Up Cycle
A warm-up cycle means that engine at temperature must
reach a minimum of 70
C (160F) and rise at least 22C
(40
F) over the course of a trip.
Freeze Frame
Freeze Frame is an element of the Diagnostic
Management System which stores various vehicle
information at the moment an emissions-related fault is
stored in memory and when the MIL is commanded on.
These data can help to identify the cause of a fault. Refer
to
Storing And Erasing Freeze Fame Data for more
detailed information.
Failure Records
Failure Records data is an enhancement of the OBD
Freeze Frame feature. Failure Records store the same
vehicle information as does Freeze Frame, but it will store
that information for any fault which is stored in on-board
memory, while Freeze Frame stores information only for
emission-related faults that command the MIL on.

6E–111 ENGINE DRIVEABILITY AND EMISSIONS
DTC P0103 – MAF Sensor Circuit High Frequency
StepActionVa l u e ( s )Ye sNo
1Was the “On-Board Diagnostic (OBD) System Check”
performed?
—Go to Step 2
Go to OBD
System
Check
21. Ignition “ON,” engine “OFF.”
2. Review and record Tech 2 Failure Records data.
3. Operate the vehicle within Failure Records
conditions as noted.
4. Using a Tech 2, monitor “DTC” info for DTC P0103.
Does the Tech 2 indicate DTC P0103 failed this
ignition?
—Go to Step 3
Refer to
Diagnostic
Aids
31. Start the engine.
2. With the engine idling, monitor “MAF Frequency”
display on the Tech 2.
Is “MAF Frequency” above the specified value?
219 g/SecGo to Step 4Go to Step 7
41. Ignition “OFF.”
2. Disconnect the MAF sensor connector.
3. Ignition “ON,” engine idling.
4. Using a Tech 2, monitor “MAF Frequency.”
Does the Tech 2 indicate a “MAF Frequency” at the
specified value?
0.0 g/SecGo to Step 5Go to Step 6
5Replace the MAF sensor.
Is the action complete?
—Verify repairGo to Step 8
61. Check the MAF harness for incorrect routing near
high voltage components (solenoids, relays,
motors).
2. If incorrect routing is found, correct the harness
routing.
Was a problem found?
—Verify repairGo to Step 7
71. With the engine idling, monitor “MAF Frequency”
display on the Tech 2.
2. Quickly snap open throttle to wide open throttle
while under a road load and record value.
Does the Tech 2 indicate “MAF Frequency” above the
specified value?
219 g/SecGo to Step 5Go to Step 8
8Replace the PCM.
IMPORTANT:The replacement PCM must be
programmed. Refer to
UBS 98model year Immobilizer
Workshop Manual.
Is the action complete?—Verify repair—

6E–251 ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P1508 IAC System Low RPM
T321115
Circuit Description
The powertrain control module (PCM) controls engine
idle speed by adjusting the position of the idle air control
(IAC) motor pintle. The IAC is a bi-directional stepper
motor driven by two coils. The PCM applies current to the
IAC coils in steps (counts) to extend the IAC pintle into a
passage in the throttle body to decrease air flow. The
PCM reverses the current to retract the pintle, increasing
air flow. This method allows highly accurate control of idle
speed and quick response to changes in engine load. If
the PCM detects a condition where too low of an idle
speed is present and the PCM is unable to adjust idle
speed by increasing the IAC counts, DTC P1508 will set,
indicating a problem with the idle control system.
Conditions for Setting the DTC
No Tech 2 test is being run.
None of these DTCs are set: TP sensor, VSS, ECT,
EGR, fuel system, MAF, MAP, IAT, canister purge,
injector control or ignition control.
Barometric pressure is above 75 kPa.
Engine coolant temperature (ECT) is above 50C
(120
F).
Engine speed is more than 100-200 RPM lower than
desired idle, based upon coolant temperature.
The engine has been running for at least 125 seconds.
Vehicle speed is less than 1 mph.
Canister purge duty cycle is above 10%.
Ignition voltage is between 9.5 volts and 16.7 volts.
The throttle is closed.
Engine speed is lower than desired idle.
All of the above conditions are met for 10 seconds.
Action Taken When the DTC Sets
The PCM will illuminate the malfunction indicator lamp
(MIL) after the second consecutive trip in which the
fault is detected.
The PCM will store conditions which were present
when the DTC was set as Freeze Frame and in the
Failure Records data.
Conditions for Clearing the MIL/DTC
DTC P1508 can be cleared by using the Tech 2 “Clear
Info” function or by disconnecting the PCM battery
feed.
Diagnostic Aids
Check for the following conditions:
Poor connection at PCM or IAC motor – Inspect
harness connectors for backed-out terminals,
improper mating, broken locks, improperly formed or
damaged terminals, and poor terminal-to-wire
connection.
Damaged harness – Inspect the wiring for damage.
Restricted air intake system – Check for a possible
collapsed air intake duct, restricted air filter element,
or foreign objects blocking the air intake system.
Throttle body – Check for objects blocking the IAC
passage or throttle bore, excessive deposits in the IAC

6E–254
ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P1509 IAC System High RPM
T321115
Circuit Description
The powertrain control module (PCM) controls engine
idle speed by adjusting the position of the idle air control
(IAC) motor pintle. The IAC is a bi-directional stepper
motor driven by two coils. The PCM applies current to the
IAC coils in steps (counts) to extend the IAC pintle into a
passage in the throttle body to decrease air flow. The
PCM reverses the current to retract the pintle, increasing
air flow. This method allows highly accurate control of idle
speed and quick response to changes in engine load. If
the PCM detect a condition where too high of an idle
speed is present and the PCM is unable to adjust idle
speed by increasing the IAC counts, DTC P1509 will set,
indicating a problem with the idle control system.
Conditions for Setting the DTC
No Tech 2 test is being run.
None of these DTCs are set: TP sensor, VSS, ECT,
EGR, fuel system, MAF, MAP, IAT, canister purge,
injector control or ignition control.
Barometric pressure is above 75 kPa.
Engine coolant temperature is above 50C (120F).
Engine speed is more than 100-200 RPM lower than
desired idle, based upon coolant temperature.
The engine has been running for at least 125 seconds.
Vehicle speed is less than 1 mph.
Canister purge duty cycle is above 10%.
Ignition voltage is between 9.5 volts and 16.7 volts.
Engine speed is lower than desired idle.
All of the above conditions are met for 5 seconds.
Action Taken When the DTC Sets
The PCM will illuminate the malfunction indicator lamp
(MIL) after the second consecutive trip in which the
fault is detected.
The PCM will store conditions which were present
when the DTC was set as Freeze Frame and in the
Failure Records data.
Conditions for Clearing the MIL/DTC
DTC P1509 can be cleared by using the Tech 2 “Clear
Info” function or by disconnecting the PCM battery
feed.
Diagnostic Aids
Check for the following conditions:
Poor connection at PCM or IAC motor – Inspect
harness connectors for backed-out terminals,
improper mating, broken locks, improperly formed or
damaged terminals, and poor terminal-to-wire
connection.
Damaged harness – Inspect the wiring for damage.
Vacuum leak – Check for a condition that causes a
vacuum leak, such as disconnected or damaged
h o s e s , l e a k s a t t h e E G R v a l v e a n d t h e E G R p i p e t o t h e
intake manifold, leaks at the throttle body, faulty or
incorrectly installed PCV valve, leaks at the intake
manifold, etc.

6E–274
ENGINE DRIVEABILITY AND EMISSIONS
Rough, Unstable, or Incorrect Idle, Stalling Symptom
StepNo Ye s Va l u e ( s ) Action
171. Check ignition coils for cracks or carbon tracking.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 18
18Using Tech 2, monitor the throttle position (TP) angle
with the engine idling.
Is the TP angle at the specified value and steady?
0%Go to Step 19
Refer to DTC
P0123
for
further
diagnosis
191. Check the positive crankcase ventilation (PCV)
valve for proper operation. Refer to
Crankcase
Ventilation System
.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 20
201. Check the transmission range switch circuit. Use
Tech 2 and be sure Tech 2 indicates that the vehicle
is in drive with the gear selector in drive or overdrive.
2. If a problem is found, diagnose and repair the
transmission range switch as necessary (refer to
4L30-E Automatic Transmission Diagnosis).
Was a problem found?
—Verify repairGo to Step 21
211. Check for the following engine mechanical items.
Refer to
Engine Mechanical for diagnosis
procedures:
EGR valve mounted backward. Compare with
a known-good vehicle.
Low compression
Sticking or leaking valves
Worn camshaft lobe(s)
Camshaft drive belt slipped or stripped
Incorrect valve timing
Worn rocker arms
Broken valve springs
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 22
221. Check for faulty motor mounts. Refer to Engine
Mechanical
for inspection of mounts.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 23
231. Review all diagnostic procedures within this table.
2. If all procedures have been completed and no
malfunctions have been found, review/inspect the
following:
Visual/physical inspection
Te c h 2 d a t a
Freeze Frame data/Failure Records buffer
All electrical connections within a suspected
circuit and/or system.
3. If a problem is found, repair as necessary.
Was a problem found?
—Verify repair
Contact
Te c h n i c a l
Assistance

6E–284
ENGINE DRIVEABILITY AND EMISSIONS
Cuts Out, Misses Symptom
StepNo Ye s Va l u e ( s ) Action
171. Check ignition coils for cracks or carbon tracking.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 18
18Using Tech 2, monitor the TP angle with the engine
idling.
Is the TP angle at the specified value and steady?
0%Go to Step 19
Refer to DTC
P0123
for
further
diagnosis
191. Check the PCV valve for proper operation. Refer to
Crankcase Ventilation System.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 20
201. Check the transmission range switch circuit. Use
Tech 2 and be sure Tech 2 indicates that the vehicle
is in drive with the gear selector in drive or overdrive.
2. If a problem is found, diagnose and repair the
transmission range switch as necessary (refer to
4L30-E Automatic Transmission Diagnosis).
Was a problem found?
—Verify repairGo to Step 21
211. Check the following engine mechanical items.
Refer to
Engine Mechanical for diagnosis
procedures:
Low compression
Sticking or leaking valves
Worn camshaft lobe(s)
Camshaft drive belt slipped or stripped
Incorrect valve timing
Worn rocker arms
Broken valve springs
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 22
221. Check for faulty motor mounts. Refer to Engine
Mechanical
for inspection of mounts.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 23
231. Review all diagnostic procedures within this table.
2. If all procedures have been completed and no
malfunctions have been found, review/inspect the
following:
Visual/physical inspection
Te c h 2 d a t a
Freeze Frame data/Failure Records butter
All electrical connections within a suspected
circuit and/or system
3. If a problem is found, repair as necessary.
Was a problem found?
—Verify repair
Contact
Te c h n i c a l
Assistance

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.