air condition OPEL FRONTERA 1998 Workshop Manual

6E–81 ENGINE DRIVEABILITY AND EMISSIONS
Engine Cranks But Will Not Run
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
2Check the 15 A ignition coil fuse, the 15 A engine fuse,
and the 30 A PCM fuse.
Was a fuse blown?
—Go to Step 3Go to Step 4
3Check for a short to ground and replace the fuse.
Is the action complete?
—Verify repair—
41. Ignition “OFF,” install a fuel pressure gauge at the
test fitting on the fuel supply line in the engine
compartment. (Use a shop cloth to absorb any fuel
leakage while making the connection.)
2. Ignition “ON,” observe the fuel pressure.
Is the fuel pressure within the specified values, and
does it hold steady?
285-376 kPa
(43-55 psi)
Go to Step 6Go to Step 5
5Is any fuel pressure indicated?
—
Go to Fuel
System
Electrical TestGo to Fuel
System
Diagnosis
6Install an injector switch box to the injector test
connector, and attempt to operate the injector.
Did the fuel pressure drop when the injector is
operated?
—Go to Step 7Go to Step 12
7Install an injector test light at the #2 cylinder injector
harness connector.
Does the light blink when the engine is cranked?
—Go to Step 8Go to Step 18
81. Ignition “ON.”
2. While the coil connectors are disconnected, touch
each coil connector’s ignition feed terminal with a
grounded test light (the ignition feed wire is black
with orange tracer).
Did the test light illuminate?
—Go to Step 10Go to Step 9
9Repair the open ignition feed circuit.
Is the action complete?
—Verify repair—
10While the coil connectors are disconnected, touch
each connector’s secondary ground terminal with a
test light to B+. (The ground wires are black.)
Did the test light illuminate at each coil connector?
—Go to Step 12Go to Step 11
11Repair the open secondary ground circuit.
Is the action complete?
—Verify repair—
121. Test the fuel for contamination.
2. If a problem is found, clean the fuel system and
correct the contaminated fuel condition as
necessary. Replace the fuel filter and replace any
injectors that are not delivering fuel (see Injector
Balance Test).
Was a problem found?
—Verify repairGo to Step 13

6E–82
ENGINE DRIVEABILITY AND EMISSIONS
Engine Cranks But Will Not Run
StepNo Ye s Va l u e ( s ) Action
131. Remove any ignition coil and install a spark tester at
the spark plug end of the coil.
2. Observe the tester while the engine is cranking.
Was a crisp, blue spark observed? Only one or two
sparks followed by no result is considered the same as
“No Spark.”
—Go to Step 15Go to Step 14
14Replace the ignition coil, and return to Step 13 to test
the remaining coils.
Is the action complete?
—Verify repair—
15Repeat Step 13 for each coil. Remove only one coil at a
time, and reinstall each coil on its spark plug after
testing, but do not refasten coils with screws at this
time.
After all coils have passed the spark test, does the
engine start?
—
Refasten all
coils with
their screws
Go to Step 16
161. Remove the spark plugs from all cylinders.
2. Visually inspect the spark plug electrodes.
3. Replace any spark plugs with loose or missing
electrodes or cracked insulators.
Did your inspection reveal any spark plugs exhibiting
excessive fouling?
—
Correct the
fouling
condition
Go to Step 17
17Refer to Engine Mechanical Diagnosis to diagnose the
following conditions:
Faulty or incorrect camshaft drive belts
Leaking or sticky valves or rings
Excessive valve deposits
Loose or worn rocker arms
Weak valve springs
Incorrect valve timing
Leaking head gasket
Is the action complete?
—Verify repairGo to Step 19
18Observe the “Engine Speed” data display on the scan
tool while cranking the engine.
Is the engine RPM indicated? (If the scan tool is
normally powered from the cigarette lighter socket, and
if the scan tool display goes blank while cranking the
engine, it will be necessary to power the scan tool
directly from the vehicle battery.)
—Go to Step 19Go to Step 28
191. Disconnect the 7-pin gray connector at the rear of
the air filter beneath the point where the air duct
attaches to the MAF sensor.
2. Ignition “ON.”
3. Using a test light connected to ground, probe the
ignition terminal at the PCM (female) side of the
7-pin connector.
Is the test light “ON?”
—Go to Step 20Go to Step 26

6E–90
ENGINE DRIVEABILITY AND EMISSIONS
Fuel System Diagnosis
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. Turn the ignition “OFF.”
2. Turn the air conditioning system “OFF.”
3. Relieve fuel system pressure and install the fuel
pressure gauge.
4. Turn the ignition “ON.”
NOTE: The fuel pump will run for approximately 2
seconds. Use Tech 2 to command the fuel pump “ON”.
5. Observe the fuel pressure indicated by the fuel
pressure gauge with the fuel pump running.
Is the fuel pressure within the specified limits?
290-376 kPa
(42-55 psi)
Go to Step 3Go to Step 17
3NOTE: The fuel pressure will drop when the fuel pump
stops running, then it should stabilize and remain
constant.
Does the fuel pressure indicated by the fuel pressure
gauge remain constant?
—Go to Step 4Go to Step 12
41. When the vehicle is at normal operation
temperature, turn the ignition “ON” to build fuel
pressure and observe the measurement on the
gauge.
2. Start the engine and observe the fuel pressure
gauge.
Did the reading drop by the amount specified after the
engine was started?
21-105 kPa
(3-15 psi)
Go to Step 5Go to Step 9
5Is fuel pressure dropping off during acceleration,
cruise, or hard cornering?
—Go to Step 6
Check for
improper fuel
6Visually and physically inspect the following items for a
restriction:
The in-pipe fuel filter.
The fuel feed line.
Was a restriction found?
—Verify repairGo to Step 7
7Remove the fuel tank and visually and physically
inspect the following items:
The fuel pump strainer for a restriction.
The fuel line for a leak.
Verify that the correct fuel pump is in the vehicle.
Was a problem found in any of these areas?
—Verify repairGo to Step 8
8Replace the fuel pump.
Is the action complete?
—Verify repair—
91. Disconnect the vacuum hose from the fuel pressure
regulator.
2. With the engine idling, apply 12-14 inches of
vacuum to the fuel pressure regulator.
Does the fuel pressure indicated by the fuel pressure
gauge drop by the amount specified?
21-105 kPa
(3-15 psi)
Go to Step 10Go to Step 11

6E–94
ENGINE DRIVEABILITY AND EMISSIONS
Idle Air Control (IAC) System Check
StepActionVa l u e ( s )Ye sNo
11. Ignition “OFF.”
2. Connect the Tech 2.
3. Set the parking brake.
4. Block the wheels.
5. Turn the air conditioning “OFF.”
6. Idle the engine in Park (A/T) or Neutral (M/T).
7. Operate the IAC test.
8. The engine speed should decrease and increase as
the IAC is cycled.
Does the RPM change?
—Go to Step 2Go to Step 3
2RPM should change smoothly.
Does the RPM change within the range specified?700-1500
RPM
—Go to Step 3
3Check the IAC passages.
Are the IAC passages OK?
—Go to Step 4Go to Step 5
4Clear any obstruction from the IAC passages.
Is the action complete?
—Verify repair—
5Replace the IAC. Refer to On-Vehicle Service, Idle Air
Control Valve.
Is the action complete?—Verify repair—

6E–97 ENGINE DRIVEABILITY AND EMISSIONS
Exhaust Gas Recirculation (EGR) System Check
D06RW106
Circuit Description
A properly operation exhaust gas recirculation (EGR)
system will directly affect the air/fuel requirements of the
engine. Since the exhaust gas introduced into the air/fuel
mixture is an inert gas (contains very little or no oxygen),
less fuel is required to maintain a correct air/fuel ratio.
Introducing exhaust gas into the combustion chamber
lowers combustion temperatures and reduces the
formation of oxides of nitrogen (NOx) in the exhaust gas.
Lower combustion temperatures also prevent detonation.
If the EGR pintle were to stay closed, the inert exhaust
gas would be replaced with air and the air/fuel mixture
would be leaner. The powertrain control module (PCM)
would compensate for the lean condition by adding fuel,
resulting in higher long term fuel trim values.
Diagnostic Aids
The EGR valve chart is a check of the EGR system. An
EGR pintle constantly in the closed position could cause
detonation and high emissions of NOx. It could also result
in high long term fuel trim values in the open throttle cell,
but not in the closed throttle cell. An EGR pintle
constantly in the open position would cause a rough idle.
Also, an EGR mounted incorrectly (rotated 180
) could
cause rough idle. Check for the following items:
EGR passages – Check for restricted or blocked EGR
passages.
Manifold absolute pressure sensor – A manifold
absolute pressure sensor may shift in calibration
enough to affect fuel delivery. Refer to
Manifold
Absolute Pressure Output Check.

6E–104
ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0101 MAF System Performance
D06RW103
Circuit Description
The mass air flow (MAF) sensor measures the amount of
air which passes through it into the engine during a given
time. The powertrain control module (PCM) uses the
mass air flow information to monitor engine operating
conditions for fuel delivery calculations. A large quantity
of air entering the engine indicates an acceleration or high
load situation, while a small quantity or air indicates
deceleration or idle.
The MAF sensor produces a frequency signal which can
be monitored using a Tech 2. DTC P0101 will be set if the
signal from the MAF sensor does not match a predicted
value based on throttle position and engine RPM.
Conditions for Setting the DTC
The engine is running.
No TP sensor or MAP sensor DTCs are set.
The throttle is steady, TP angle doesn’t change by
more than 1%.
System voltage is between 11.5 volts and 16 volts.
Calculated air flow is between 25 g/second and 40
g/second.
Above conditions present for at least 1 second.
MAF signal frequency indicates an airflow significantly
higher or lower than a predicted value based on throttle
position and engine RPM for a total of 12.5 seconds
over a 25-second period of time.
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 calculates an airflow value based on idle air
control valve position, throttle position, RPM and
barometric pressure.
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 P0101 can be cleared by using the Tech 2 “Clear
Info” function or by disconnecting the PCM battery
feed.
Diagnostic Aids
An intermittent may be caused by the following:
Poor connections.
Mis-routed harness.
Rubbed through wire insulation.
Broken wire inside the insulation.
Refer to Intermittents under service category Symptoms.
Any un-metered air may cause this DTC to set. Check for
the following:
The duct work at the MAF sensor for leaks.
An engine vacuum leak.
The PCV system for vacuum leaks.
An incorrect PCV valve.

6E–105 ENGINE DRIVEABILITY AND EMISSIONS
The engine oil dip stick not fully seated.
The engine oil fill cap loose or missing.
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart.
2. The MAF system performance or “rationality”
diagnostic uses the MAP sensor signal along with
other input to calculate an expected airflow rate that
is then compared to the actual measured airflow
from the MAF sensor. The first few steps of this
table verify that the MAP sensor is working properly.
6. Using Freeze Frame and/or Failure Records data
may aid in locating an intermittent condition. If the
DTC cannot be duplicated, the information included
in the Freeze Frame and/or Failure Records data
can be useful in determining how many miles since
the DTC set. The Fail Counter and Pass Counter
can also be used to determine how many ignition
cycles the diagnostic reported a pass and/or a fail.
Operate the vehicle within the same Freeze Frame
conditions (RPM, load, vehicle speed , temperature,
etc.) that were noted. This will isolate when the
DTC failed.For any test that requires back probing the PCM or
component harness connectors, use the Connector
Test Adapter Kit J 35616-A. Using this kit will
prevent any damage to the harness connector
terminals.
7. Any un-metered air may cause this DTC to set.
Check the PVC system for vacuum leaks. Also
inspect the dip stick for being pulled out. Check the
oil fill cap for being loose.
8. Verifies the signal circuit from the MAF sensor
electrical connector to the PCM.
9. Verifies whether a ground and B+ circuit is available.
10. Checks a signal circuit for an open.
11. Checks for a signal circuit shorted to B+.
DTC P0101 – MAF System Performance
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. Using a Tech 2, select “MAP” from the Engine 1
Data List.
Is the value displayed greater than the value shown?
85 kPaGo to Step 3Go toStep 13
31. Remove the MAP sensor from the intake manifold
but leave the electrical harness connected.
2. Connect a hand operated vacuum pump to the MAP
sensor.
3. Observe the MAP display while slowly applying
vacuum up to 20” Hg as indicated on the pump
gauge.
Each 1” of vacuum applied should result in a 3 to 4 kPa
drop in the MAP sensor value on the Tech 2 and the
value should change smoothly with each increase in
vacuum.
Did the MAP value change smoothly through the entire
range of the test without any erratic readings?
—Go to Step 13Go to Step 4
4With 20” Hg vacuum applied to the MAP sensor, is the
MAF sensor reading the same or less than the value
shown?
34 kPaGo to Step 5Go to Step 13
5Disconnect the vacuum source from the MAP sensor.
Does the MAP sensor reading return to its original
value?
—Go to Step 6Go to Step 13

6E–106
ENGINE DRIVEABILITY AND EMISSIONS
DTC P0101 – MAF System Performance
StepNo Ye s Va l u e ( s ) Action
61. Ignition “ON,” engine “OFF.”
2. Review the Freeze Frame and/or Failure Records
data for this DTC and note parameters.
3. Ignition “OFF” for 15 seconds.
4. Start the engine and operate the vehicle within the
conditions required for this diagnostic to run, and as
close to the conditions recorded in Freeze Frame
/Failure Records possible. (Special operating
conditions that need to be met before the PCM will
run this diagnostic (where applicable) are listed in
“Conditions for Setting the DTC”).
5. Using the Tech 2, select “DTC,” then enter the DTC
number which was set.
Does the Tech 2 indicate that this diagnostic failed this
ignition?
—Go to Step 7
Refer to
Diagnostic
Aids
71. Check for the following conditions:
Objects blocking the MAF sensor inlet screen;
Intake manifold vacuum leaks;
Vacuum leaks at throttle body;
Vacuum leaks EGR value flange and pipes.
Crankcase ventilation valve faulty, missing, or
incorrectly installed.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo toStep 8
81. Ignition “OFF.”
2. Disconnect the MAF sensor connector.
3. Ignition “ON,” engine “OFF.”
4. Using DVM 5-8840-0285-0, measure voltage
between the MAF sensor signal circuit and chassis
ground.
Is the voltage near the specified value?
5 VGo to Step 9Go toStep 10
9Connect a test light (5-8840-0607-0) between the MAF
sensor ignition feed and ground circuits at the MAF
sensor harness connector.
Is the test light “ON?”
—Go to Step 13Go toStep 12
10Is the voltage less than the specified value?4.5 VGo to Step 13Go toStep 11
111. Ignition “OFF,” disconnect the PCM.
2. Ignition “ON,” engine “OFF.”
3. Measure voltage between the MAF signal circuit
and ground.
Does the voltage measure near the specified value?
0 VGo to Step 13Go toStep 12
12Connect a test light (5-8840-0607-0) between the MAF
sensor ignition feed circuit and chassis ground.
Is the test light “ON?”
—Go to Step 13Go toStep 7
131. Check for a poor connection at the MAF sensor.
2. If a poor connection is found, replace faulty
terminal(s). Refer to
Repair Procedures in
Electrical Diagnosis (8A Cell 5).
Was a poor connection found?—Verify repairSolved

6E–107 ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0102 MAF Sensor Circuit Low Frequency
T321122
Circuit Description
The mass air flow (MAF) sensor measures the amount of
air which passes through it into the engine during a given
time. The powertrain control module (PCM) uses the
mass air flow information to monitor engine operating
conditions for fuel delivery calculations. A large quantity
of air entering the engine indicates an acceleration or high
load situation, while a small quantity of air indicates
deceleration or idle.
The MAF sensor produces a frequency signal which can
be monitored using a Tech 2. The frequency will vary
within a range of around 2500 Hz at idle to around
1900 Hz at maximum engine load. DTC P0102 will be set
if the signal from the MAF sensor is below the possible
range of a normally operating MAF sensor.
Conditions for Setting the DTC
The engine is running above 500 RPM for greater than
10 seconds.
System voltage is above 11.5 volts.
MAF signal frequency is below 1000 Hz for a total of
50-percent of the last 1000 samples monitored. A
sample is taken every cylinder event.
Action Taken When the DTC Sets
The PCM will illuminate the malfunction indicator lamp
(MIL) the first time the fault is detected.
The PCM calculates an air flow value based on idle air
control valve position, throttle position, RPM and
barometric pressure.
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 P0102 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 – Inspect harness connectors
for backed-out terminals, improper mating, broken
locks, improperly formed or damaged terminals, and
poor terminal-to-wire connection.
Misrouted harness – Inspect the MAF sensor harness
to ensure that it is not routed too close to high voltage
wires.
Damaged harness – Inspect the wiring harness for
damage. If the harness appears to be OK, observe the
Tech 2 while moving connectors and wiring harnesses
related to the MAF sensor. A change in the display will
indicate the location of the fault.
Plugged intake air duct or filter element – A wide-open
throttle acceleration from a stop should cause the
mass air flow displayed on a Tech 2 to increase from
about 3-6 g/second at idle to 100 g/second or greater
at the time of the 1-2 shift. If not, check for a restriction.
If DTC P0102 cannot be duplicated, the information
included in the Failure Records data can be useful in
determining vehicle mileage since the DTC was last set.

6E–108
ENGINE DRIVEABILITY AND EMISSIONS
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart.
2. This step verifies that the problem is present at idle.4. A voltage reading of less than 4 or over 5 volts at the
MAF sensor signal circuit indicates a fault in the
wiring or a poor connection.
5. This verifies that ignition feed voltage and a good
ground are available at the MAF sensor.
DTC P0102 – MAF Sensor Circuit Low 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. Start the engine.
2. With the engine idling, monitor “MAF Frequency”
display on the Tech 2.
Is the “MAF Frequency” below the specified value?
3g/SecGo to Step 4Go to Step 5
31. 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 P0102.
Does the Tech 2 indicate DTC P0102 failed this
ignition?
—Go to Step 4
Refer to
Diagnostic
Aids
41. Ignition “OFF.”
2. Disconnect the MAF sensor connector.
3. Ignition “ON,” engine “OFF.”
4. Using a DVM, measure voltage between the MAF
sensor signal circuit and battery ground.
Is the voltage near the specified value?
5 VGo to Step 5Go to Step 8
5Connect a test light between the MAF sensor ignition
feed and ground circuits at the MAF sensor harness
connector.
Is the test light “ON?”
—Go to Step 13Go to Step 6
6Connect a test light between the MAF sensor ignition
feed circuit and battery ground.
Is the test light “ON?”
—Go to Step 12Go to Step 7
71. Check for a poor connection at the MAF sensor.
2. If a poor connection is found, replace the faulty
terminal(s).
Was a poor connection found?
—Verify repairGo to Step 11
81. Ignition “OFF.”
2. Disconnect the MAF sensor.
3. Disconnect the PCM connector for the MAF signal
circuit.
4. Ignition “ON,” engine “OFF.”
5. With the DVM, measure the voltage between the
MAF signal terminal at the PCM and battery ground.
Is the voltage under the specified value?
4 VGo to Step 9Go to Step 10