Gas OPEL FRONTERA 1998 Workshop Manual

6E–270
ENGINE DRIVEABILITY AND EMISSIONS
Detonation/Spark Knock Symptom
StepActionVa l u e ( s )Ye sNo
1DEFINITION:
A mild to severe ping, usually worse under acceleration.
The engine makes sharp metallic knocks that change
with throttle opening.
Was the “On-Board Diagnostic (OBD) System Check”
performed?
—Go to Step 2
Go to OBD
System
Check
21. Perform a bulletin search.
2. If a bulletin that addresses the symptom is found,
correct the condition as instructed in the bulletin.
Was a bulletin found that addresses the symptom?
—Verify repairGo to Step 3
3Was a visual/physical check performed?
—Go to Step 4
Go to
Visual/Physic
al Check
4If Tech 2 readings are normal (refer to Ty p i c a l S c a n
Va lu es
) and there are no engine mechanical faults, fill
the fuel tank with a known quality gasoline that has a
minimum octane rating of 87 and re-evaluate the
vehicle performance.
Is detonation present?
—Go to Step 5Verify repair
51. 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 6
61. Check TCC operation. Refer to 4L30-E
Transmission Diagnosis
.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 7
71. Check for obvious overheating problems:
Low engine coolant.
Restricted air flow to radiator, or restricted
water flow through radiator.
Correct coolant solution should be a 50/50 mix
of approved antifreeze/coolant and water.
Refer to
Engine Cooling.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 8
81. Check fuel pressure. Refer to Chart Fuel System
Pressure Test.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 9
91. Check items that can cause an engine to run lean
(long term fuel trim significantly in the positive
range). For a lean condition, refer to
Diagnostic
Aids
in DTC P0171 Diagnostic Support.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 10

6E–273 ENGINE DRIVEABILITY AND EMISSIONS
Rough, Unstable, or Incorrect Idle, Stalling Symptom
StepNo Ye s Va l u e ( s ) Action
101. Visually/physically inspect for the following
conditions:
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 passage and on the IAC
pintle, and excessive deposits in the throttle
bore and on the throttle plate.
Large vacuum leak. Check for a condition that
causes a large vacuum leak, such as an
incorrectly installed or faulty crankcase
ventilation valve or a disconnected brake
booster hose.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 8
11Check the injector connections. If any of the injectors
are connected to an incorrect cylinder, correct as
necessary.
Was a problem found?
—Verify repairGo to Step 12
121. Perform the “Injector Coil/Balance Test” in Fuel
Metering System
.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 13
131. Check for fuel in the pressure regulator vacuum
hose.
2. If fuel is present, replace the fuel pressure regulator
assembly. Refer to
Fuel Metering System.
3. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 14
141. Check for proper ignition voltage output with spark
tester J 26792 (ST-125). Refer to
Electronic Ignition
System
for the procedure.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 15
151. Remove spark plugs. Check for wet plugs, cracks,
wear, improper gap, burned electrodes, or heavy
deposits. Refer to
Electronic Ignition System.
NOTE: If spark plugs are gas or oil fouled, the cause of
the fouling must be determined before replacing the
spark plugs.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 16
161. Check for a loose ignition coil ground.
Refer to
Electrical Ignition System.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 17

6E–275 ENGINE DRIVEABILITY AND EMISSIONS
Poor Fuel Economy Symptom
StepActionVa l u e ( s )Ye sNo
1DEFINITION:
Fuel economy, as measured by an actual road test, is
noticeably lower than expected. Also, economy is
noticeably lower than it was on this vehicle at one time,
as previously shown by an actual road test.
(Non-standard tires will cause odometer readings to be
incorrect, and that may cause fuel economy to appear
poor when it is actually normal.)
Was the “On-Board Diagnostic (OBD) System Check”
performed?
—Go to Step 2
Go to OBD
System
Check
21. Perform a bulletin search.
2. If a bulletin that addresses the symptom is found,
correct the condition as instructed in the bulletin.
Was a bulletin found that addresses the symptom?
—Verify repairGo to Step 3
3Was a visual/physical check performed?
—Go to Step 4
Go to
Visual/Physic
al Check
4Check owner’s driving habits.
Is the A/C “ON” full time (defroster mode “ON”)?
Are tires at the correct pressure?
Are excessively heavy loads being carried?
Is acceleration too much, too often?
Was a problem found?
—Go to Step 5Go to Step 6
5Review the items in Step 4 with the customer and
advise as necessary.
Is the action complete?
—System OK—
61. Visually/physically check: Vacuum hoses for splits,
kinks, and improper connections and routing as
shown on the “Vehicle Emission Control
Information” label.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 7
71. Remove and check the air filter element for dirt or for
restrictions. Refer to
Air Intake System.
2. Replace the air filter element if necessary.
Was a repair required?
—Verify repairGo to Step 8
81. Remove spark plugs and check for wet plugs,
cracks, wear, improper gap, burned electrodes, or
heavy deposits. Refer to
Spark Plug Replacement.
NOTE: If spark plugs are gas or oil fouled, the cause of
the fouling must be determined before replacing the
spark plugs.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 9
91. Check for low engine coolant level. Refer to Engine
Cooling
.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 10

6E–280
ENGINE DRIVEABILITY AND EMISSIONS
Backfire Symptom
StepActionVa l u e ( s )Ye sNo
1DEFINITION:
Fuel ignites in the intake manifold, or in the exhaust
system, making a loud popping noise.
Was the “On-Board Diagnostic (OBD) System Check”
performed?
—Go to Step 2
Go to OBD
System
Check
21. Perform a bulletin search.
2. If a bulletin that addresses the symptom is found,
correct the condition as instructed in the bulletin.
Was a bulletin found that addresses the symptom?
—Verify repairGo to Step 3
3Was a visual/physical check performed?
—Go to Step 4
Go to
Visual/Physic
al Check
41. Check for proper ignition voltage coil output with
spark tester 5-8840-0383-0. Refer to
Electric
Ignition System
for procedure.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 5
51. Remove spark plugs and check for wet plugs,
cracks, wear, improper gap, burned electrodes, or
heavy deposits. Refer to
Electronic Ignition
System
.
NOTE: If spark plugs are gas or oil fouled, the cause of
the fouling must be determined before replacing the
spark plugs. Refer to
DTC P0172 to determine the
cause of a rich condition or
Engine Mechanical for an oil
fouling condition.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 6
61. Visually/physically inspect the ignition coils for
cracks.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 7
71. Check for an intermittent ignition system
malfunction:
Intermittent CKP 58X signal.
Intermittent ignition feed circuit or sensor
ground circuit to the crankshaft position
sensor.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 8
81. Check the fuel pressure. Refer to Fuel System
Pressure Test
.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 9

6E–283 ENGINE DRIVEABILITY AND EMISSIONS
Cuts Out, Misses Symptom
StepNo Ye s Va l u e ( s ) Action
101. Visually/physically inspect for the following
conditions:
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 passage and on the IAC
pintle, and excessive deposits in the throttle
bore and on the throttle plate.
Large vacuum leak. Check for a condition that
causes a large vacuum leak, such as an
incorrectly installed or faulty PCV valve or
brake booster hose disconnected .
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 8
11Check the injector connections. If any of the injectors
are connected to an incorrect cylinder, correct as
necessary.
Was a problem found?
—Verify repairGo to Step 12
121. Perform the “Injector Coil/Balance Test” in Fuel
Metering System
.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 13
131. Check for fuel in the pressure regulator vacuum
hose.
2. If fuel is present, replace the fuel pressure regulator
assembly. Refer to
Fuel Metering System.
3. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 14
141. Check for proper ignition voltage output with spark
tester J 26792 (ST-125). Refer to
Electronic Ignition
System
for the procedure.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 15
151. Remove spark plugs. Check for wet plugs, cracks,
wear, improper gap, burned electrodes, or heavy
deposits. Refer to
Electronic Ignition System.
NOTE: If spark plugs are gas or oil fouled, the cause of
the fouling must be determined before replacing the
spark plugs.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 16
161. Check for a loose ignition coil ground.
Refer to
Electronic Ignition System.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 17

6E–286
ENGINE DRIVEABILITY AND EMISSIONS
Hesitation, Sag, Stumble Symptom
StepNo Ye s Va l u e ( s ) Action
101. Check for proper ignition voltage output with spark
tester J 26792 (ST-125). Refer to
Electronic Ignition
System
for the procedure.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 11
111. Check for a loose ignition coil ground.
Refer to
Electronic Ignition System.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 12
121. Check the ignition coils for cracks or carbon
tracking.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 13
131. Remove spark plugs and check for wet plugs,
cracks, wear, improper gap, burned electrodes, or
heavy deposits. Refer to
Electronic Ignition
System
.
NOTE: If spark plugs are gas or oil fouled, the cause of
the fouling must be determined before replacing the
spark plugs.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 14
141. Check the PCM grounds for clearness, tightness
and proper routing. Refer to the PCM wiring
diagrams in Electrical Diagnosis.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 15
151. Check the MAF sensor connections.
2. If a problem is found, replace the faulty terminals as
necessary. Refer to
Electrical Diagnosis for wiring
repair procedures.
Was a problem found?
—Verify repairGo to Step 16
161. Visually/physically check vacuum hoses for splits,
kinks, and proper connections and routing as
shown on the “Vehicle Emission Control
Information” label.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 17

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–318
ENGINE DRIVEABILITY AND EMISSIONS
2. Remove the fuel pump relay from the underhood
relay box. Refer to
Fuel Pump Relay.
TS23976R
3. Start the engine and allow it to stall.
4. Crank the engine for 30 seconds.
5. Disconnect the negative battery cable.
Fuel Pump Assembly
Removal Procedure
1. Disconnect the negative battery cable.
2. Drain all the fuel from the tank.
3. Install and tighten the drain plug.
Tighten
Tighten the drain plug to 20 Nꞏm (14 lb ft.).
4. Remove the fuel tank. Refer to
Fuel Tank.
5. Remove the retaining screws from the fuel tank.
6. Remove the fuel pump assembly from the fuel tank.
Cover the fuel pump opening in order to prevent
dust, dirt, or debris from entering the fuel tank.
TS23795
Inspection Procedure
1. Inspect the fuel pump gasket for tears, cracks,
stretching, or rotting. If any of these conditions are
found, replace the fuel pump gasket.
2. Inspect the in-tank fuel filter for tears or evidence of
dirt, debris, or water in the fuel. If any of these
conditions are found, replace the in-tank fuel filter.
Installation Procedure
1. Install the fuel pump assembly.
2. Install the fuel pump assembly retaining screws.
3. Install the fuel tank assembly. Refer to
Fuel Tank.
4. Fill the tank with fuel.
5. Tighten the fuel filler cap.
6. Connect the negative battery cable.
TS23795

6E–323 ENGINE DRIVEABILITY AND EMISSIONS
11. Connect the fuel filler fuse at the tank.
12. Connect the air breather hose at the tank.
TS23796
13. Fill the fuel tank with fuel.
14. Tighten the fuel filler cap.
15. Connect the negative battery cable.
Throttle Body (TB)
Removal Procedure
1. Disconnect the negative battery cable.
2. Drain the cooling system. Refer to
Cooling System.
3. Remove the accelerator cable assembly. Refer to
Accelerator Cable in Engine Speed Control System..
4. Disconnect the electrical connectors:
Throttle position (TP) sensor.
Idle air control (IAC) solenoid.
Intake air temperature (IAT) sensor. Refer to
Intake Air Temperature Sensor.
035RW023
5. Disconnect the vacuum hose below the air horn.
6. Remove the intake air duct clamp.
7. Disconnect the intake air duct.
8. Disconnect the coolant lines from the throttle body.
9. Remove the bolts from the common chamber.
10. Remove the throttle body from the common chamber.
11. Remove the gasket from the upper intake manifold.
035RW024
12. Remove the IAC. Refer to Idle Air Control (IAC)
Solenoid
.
13. Remove the TP sensor. Refer to
Throttle Position
(TP) Sensor
.
Inspection Procedure
NOTE: Do not use solvent of any type when you clean the
gasket surfaces on the intake manifold and the throttle
body assembly. The gasket surfaces and the throttle
body assembly may be damaged as a result.
If the throttle body gasket needs to be replaced,
remove any gasket material that may be stuck to the
mating surfaces of the manifold.
Do not leave any scratches in the aluminum casting.
Installation Procedure
1. Install the TP sensor. Refer to Throttle Position (TP)
Sensor
.
2. Install the IAC. Refer to
Idle Air Control (IAC)
Solenoid
.
3. Install the gasket on the common chamber.
4. Install the throttle body on the common chamber.

6E–324
ENGINE DRIVEABILITY AND EMISSIONS
5. Secure the gasket and the throttle body with the four
bolts.
The vacuum lines must be properly routed under
the throttle body before tightening the mounting
bolts.
Tighten
Tighten the throttle body mounting bolts to 24 Nꞏm
(17 lb ft.).
035RW024
6. Install the coolant lines.
7. Connect all the vacuum lines.
8. Install the intake air duct.
9. Tighten the intake air duct clamp.
10. Connect all the electrical connectors:
Throttle position (TP) sensor.
Idle air control (IAC) solenoid.
Intake air temperature (IAT) sensor. Refer to
Intake Air Temperature Sensor.
035RW023
11. Install the accelerator cable assembly. Refer to
Accelerator Cable in Engine Speed Control System..
12. Fill the cooling system. Refer to
Cooling System.
13. Install the negative battery cable.
Electronic Ignition System
Removal Procedure
1. Disconnect the negative battery cable.
2. Disconnect the electrical connector at the ignition coil.
3. Remove the two screws that secure the ignition coil to
the rocker cover.
014RW108
4. Remove the ignition coil and the spark plug boot from
the spark plug.
Twist the ignition coil while pulling it straight up.
014RW091
5. Use the spark plug socket in order to remove the
spark plug from the engine.