1998 OPEL FRONTERA light

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–83 ENGINE DRIVEABILITY AND EMISSIONS
Engine Cranks But Will Not Run
StepNo Ye s Va l u e ( s ) Action
201. At the PCM (female) side of the connector, connect
a test light between the ignition + terminal and one
of the injector driver circuits at the same connector.
2. Ignition “ON.”
3. Observe the test light, and repeat the test for each
injector driver circuit.
Did the test light stay on when checking any of the 6
injector driver circuits?
—Go to Step 21Go to Step 23
211. Ignition “OFF,” disconnect the PCM.
2. Ignition “ON,” observe the test light.
Is the test light “ON?”
—Go to Step 22Go to Step 27
22Locate and repair the short to ground in the injector
driver circuit.
Is the action complete?
—Verify repair—
231. Using the same test location as in step 20, connect
a test light between the ignition terminal and one of
the driver circuits.
2. Crank the engine and observe the test light.
3. Repeat for each injector driver circuit.
Did the light blink during the test for each circuit?
—Go to Step 25Go to Step 24
24Check for an open injector driver circuit.
Was a problem found?
—Verify repairGo to Step 27
251. At the injector (male) side of the gray connector,
connect an ohmmeter between the ignition pin and
one of the driver circuit pins.
2. Check for continuity in the circuit.
3. Repeat for each injector circuit. The readings
should be approximately equal to the specified
value for injector resistance.
Was a problem found?
12.5 ohmsVerify repairGo to Step 8
26Repair the ignition feed circuit.
Is the action complete?
—Verify repair—
27Replace the PCM.
IMPORTANT:The replacement PCM must be
programmed. Refer to
UBS 98model year Immobilizer
Workshop Manual.
Is the action complete?—Verify repair—
281. Raise the vehicle and disconnect the CKP sensor
harness.
2. Ignition “ON.”
3. With a test light to ground, probe the harness
ignition feed terminal.
Did the light illuminate?
—Go to Step 30Go to Step 29
29Check the ignition feed wire between the sensor and
the PCM for a short to ground or open circuit.
Is the action complete?
—Verify repair—

6E–84
ENGINE DRIVEABILITY AND EMISSIONS
Engine Cranks But Will Not Run
StepNo Ye s Va l u e ( s ) Action
301. Ignition “ON.”
2. At the CKP harness connector, connect a test light
between the ignition and ground terminals.
Did the light illuminate?
—Go to Step 32Go to Step 31
31Check the sensor ground circuit for an open or short to
voltage.
Is the action complete?
—Verify repair—
32Check the signal circuit between the sensor and the
PCM for a short to ground, short to voltage, or an open.
Was a problem found?
—Verify repairGo to Step 33
33Replace the CKP sensor.
Is the action complete?
—Verify repairGo to Step 27

6E–86
ENGINE DRIVEABILITY AND EMISSIONS
CAUTION: To reduce the risk of fire and personal
injury:
It is necessary to relieve fuel system pressure
before connecting a fuel pressure gauge. Refer to
Fuel Pressure Relief Procedure, below.
A small amount of fuel may be released when
disconnecting the fuel lines. Cover fuel line
fittings with a shop towel before disconnecting, to
catch any fuel that may leak out. Place the towel in
an approved container when the disconnect is
completed.
Fuel Pressure Relief Procedure
1. Remove the fuel cap.
2. Remove the fuel pump relay from the underhood
relay center.
3. Start the engine and allow it to stall.
4. Crank the engine for an additional 3 seconds.
Fuel Gauge Installation
1. Remove the shoulder fitting cap.
2. Install fuel gauge 5-8840-0378-0 to the fuel feed line
located in front of and above the right side valve train
cover .
3. Reinstall the fuel pump relay.
Fuel System Electrical Test
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. Read the “Caution” above.
2. Relieve the fuel system pressure and install the fuel
pump pressure gauge to the test fitting.
3. Use Tech 2 to command the fuel pump “ON.”
Is there an immediate pressure build-up which
indicates the pump is running?
—Go to Step 3Go to Step 4
31. Verify that the pump is not running by removing the
fuel filler cap and listening.
2. Command the pump “ON” with Tech 2.
Did the pump turn “OFF” after 2 seconds?
—
Te s t
completed
Go to Step 12
41. Ignition “OFF.”
2. Remove the fuel pump relay.
3. Using a test light connected to ground, probe the
battery feed to the relay.
Did the light illuminate?
—Go to Step 6Go to Step 5
5Repair short or open battery feed to fuel pump relay.
Is the action complete?
—Verify repair—
61. Connect a test light between the two wires that
connect to the fuel pump relay pull-in coil.
2. Ignition “ON.”
Did the test light illuminate for 2 seconds and then turn
off?
—Go to Step 12Go to Step 7
71. With a test light connected to battery (–), probe the
fuel pump relay connector at the wire which runs
from the relay pull-in coil to the PCM.
2. Ignition “ON.”
Did the test light illuminate for 2 seconds and then turn
off?
—Go to Step 8Go to Step 9
8Locate and repair open in the fuel pump relay ground
circuit.
Is the action complete?
—Verify repair—

6E–87 ENGINE DRIVEABILITY AND EMISSIONS
Fuel System Electrical Test
StepNo Ye s Va l u e ( s ) Action
9Check for short or open between the PCM and the fuel
pump relay.
Was a problem found?
—Verify repairGo to Step 10
101. Check the fuel pump relay circuit for a poor terminal
connection at the PCM.
2. If a problem is found, replace terminal as necessary.
Was a problem found?
—Verify repairGo to Step 11
11Replace the PCM.
IMPORTANT:The replacement PCM must be
programmed. Refer to
UBS 98model year Immobilizer
Workshop Manual.
Is the action complete?—Verify repair—
121. Reconnect the fuel pump relay.
2. Disconnect the fuel pump electrical connector at the
fuel tank.
3. Using a test light connected to ground, probe the
fuel pump feed wire (harness side).
4. Command the fuel pump “ON” with Tech 2.
Did the light illuminate for 2 seconds?
—Go to Step 15Go to Step 13
131. Honk the horn to verify that the horn relay is
functioning.
2. Substitute the horn relay for the fuel pump relay.
3. Leave the test light connected as in step 12.
4. Command the fuel pump “ON” with Tech 2.
Did the test light illuminate for 2 seconds when the fuel
pump was commanded “ON?”
—Go to Step 17Go to Step 14
141. Re-connect the horn relay in its proper location.
2. Check for a short circuit, blown fuse or open circuit
between the relay and the fuel tank.
Is the action complete?
—Verify repair—
151. With the fuel pump electrical connector at the fuel
tank disconnected, connect a test light between the
feed wire and the ground wire (harness side).
2. Command the fuel pump “ON” with Tech 2.
Did the test light illuminate for 2 seconds?
—Go to Step 18Go to Step 16
16Repair the open circuit in the fuel pump ground wire.
Is the action complete?
—Verify repair—
171. Re-connect the horn relay in its proper location.
2. Replace the fuel pump relay.
Is the action complete?
—Verify repair—
18Replace the fuel pump.
Is the action complete?
—Verify repair—

6E–89 ENGINE DRIVEABILITY AND EMISSIONS
The valve or valve seat within the fuel pressure
regulator.
The fuel injector(s).
4. Fuel pressure that drops off during acceleration,
cruise, or hard cornering may case a lean condition.
A lean condition can cause a loss of power, surging,
or misfire. A lean condition can be diagnosed using
a Tech II Tech 2. If an extremely lean condition
occurs, the oxygen sensor(s) will stop toggling. The
oxygen sensor output voltage(s) will drop below 500
mV. Also, the fuel injector pulse width will increase.
IMPORTANT:Make sure the fuel system is not
operating in the “Fuel Cut-Off Mode.”
When the engine is at idle, the manifold pressure is
low (high vacuum). This low pressure (high vacuum)
is applied to the fuel pressure regulator diaphragm.
The low pressure (high vacuum) will offset the
pressure being applied to the fuel pressure regulator
diaphragm by the spring inside the fuel pressure
regulator. When this happens, the result is lower fuel
pressure. The fuel pressure at idle will vary slightly as
the barometric pressure changes, but the fuel
pressure at idle should always be less than the fuel
pressure noted in step 2 with the engine “OFF.”
16.Check the spark plug associated with a particular
fuel injector for fouling or saturation in order to
determine if that particular fuel injector is leaking. If
checking the spark plug associated with a particular
fuel injector for fouling or saturation does not
determine that a particular fuel injector is leaking,
use the following procedure:
Remove the fuel rail, but leave the fuel lines and
injectors connected to the fuel rail. Refer to
Fuel Rail
Assembly
in On-Vehicle Service.
Lift the fuel rail just enough to leave the fuel injector
nozzles in the fuel injector ports.
CAUTION: In order to reduce the risk of fire and
personal injury that may result from fuel spraying on
the engine, verify that the fuel rail is positioned over
the fuel injector ports and verify that the fuel injector
retaining clips are intact.
Pressurize the fuel system by connecting a 10 amp
fused jumper between B+ and the fuel pump relay
connector.
Visually and physically inspect the fuel injector
nozzles for leaks.
17.A rich condition may result from the fuel pressure
being above 376 kPa (55 psi). A rich condition may
cause a DTC P0132 or a DTC P0172 to set.
Driveability conditions associated with rich
conditions can include hard starting (followed by
black smoke) and a strong sulfur smell in the
exhaust.20.This test determines if the high fuel pressure is due
to a restricted fuel return line or if the high fuel
pressure is due to a faulty fuel pressure regulator.
21.A lean condition may result from fuel pressure
below 333 kPa (48 psi). A lean condition may
cause a DTC P0131 or a DTC P0171 to set.
Driveability conditions associated with lean
conditions can include hard starting (when the
engine is cold ), hesitation, poor driveability, lack of
power, surging , and misfiring.
22.Restricting the fuel return line causes the fuel
pressure to rise above the regulated fuel pressure.
Command the fuel pump “ON” with Tech 2. The fuel
pressure should rise above 376 kPa (55 psi) as the
fuel return line becomes partially closed.
NOTE: Do not allow the fuel pressure to exceed 414 kPa
( 6 0 p s i ) . F u e l p r e s s u r e i n e x c e s s o f 4 1 4 k P a ( 6 0 p s i ) m a y
damage the fuel pressure regulator.
CAUTION: To reduce the risk of fire and personal
injury:
It is necessary to relieve fuel system pressure
before connecting a fuel pressure gauge. Refer to
Fuel Pressure Relief Procedure, below.
A small amount of fuel may be released when
disconnecting the fuel lines. Cover fuel line
fittings with a shop towel before disconnecting, to
catch any fuel that may leak out. Place the towel in
an approved container when the disconnect is
completed.
Fuel Pressure Relief Procedure
1. Remove the fuel cap.
2. Remove the fuel pump relay from the underhood
relay center.
3. Start the engine and allow it to stall.
4. Crank the engine for an additional 3 seconds.
Fuel Gauge Installation
1. Remove the shoulder fitting cap.
2. Install fuel gauge 5-8840-0378-0 to the fuel feed line
located in front of and above the right side valve train
cover.
3. Reinstall the fuel pump relay.

6E–93 ENGINE DRIVEABILITY AND EMISSIONS
Idle Air Control (IAC) System Check
Circuit Description
The powertrain control module (PCM) controls engine
idle speed with the idle air control (IAC) valve. To increase
idle speed, the PCM retracts the IAC valve pintle away
from its seat, allowing more air to bypass the throttle bore.
To decrease idle speed, it extends the IAC valve pintle
towards its seat, reducing by pass air flow. Tech 2 will
read the PCM commands to the IAC valve in counts.
Higher counts indicate more air bypass (higher idle).
Lower counts indicate less air is allowed to bypass (lower
idle).
Diagnostic Aids
A slow, unstable, or fast idle may be caused by a non-IAC
system problem that cannot be overcome by the IAC
valve. Out of control range IAC Tech 2 counts will be
above 60 if idle is too low, and zero counts if idle is too
high. The following checks should be made to repair a
non-IAC system problem:
Vacuum leak (high idle) – If idle is too high, stop the
engine. Fully extend (low) IAC with the Tech 2. Start
the engine. If idle speed is above 800 RPM, locate and
correct the vacuum leak, including the PCV system.
Check for binding of the throttle blade or linkage.
Lean heated oxygen sensor signal (high air/fuel ratio) –
The idle speed may be too high or too low. Engine
speed may vary up and down, and disconnecting the
IAC valve does not help. Diagnostic trouble codes
P0131, P0151, P0171, or P0174 may be set. Tech 2
oxygen (O2) voltage will be less than 100 mV (0.1 V).
Check for low regulated fuel pressure, water in fuel, or
a restricted injector.
Rich heated oxygen sensor signal (low air/fuel ratio) –
The idle speed will be too low. Tech 2 IAC counts will
usually be above 80. The system is obviously rich and
may exhibit black smoke in the exhaust.
Tech 2 O2 voltage will be fixed at about 750 mV (0.75
V). Check for high fuel pressure, or a leaking or
sticking injector. A silicon-contaminated heated
oxygen sensor will show an O2 voltage slow to
respond on Tech 2.
Throttle body – Remove the IAC valve and inspect the
bore for foreign material.
IAC valve electrical connections – IAC valve
connections should be carefully checked for proper
contact.
PCV valve – An incorrect or faulty PCV valve may
result in an incorrect idle speed. Refer to
Diagnosis,
Rough Idle, Stalling.
If intermittent poor driveability or
idle symptoms are resolved by disconnecting the IAC,
carefully recheck the connections and valve terminal
resistance, or replace the IAC.
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart.
1. The Tech 2 is used to extend and retract the IAC
valve. Valve movement is verified by an engine
speed change. If no change in engine speed
occurs, the valve can be resettled when removed
from the throttle body.
2. This step checks the quality of the IAC movement in
step 1. Between 700 revolutions per minute (RPM)
and about 1500 RPM, the engine speed should
change smoothly with each flash of the tester light
in both extend and retract. If the IAC valve is
retracted beyond the control range (about 1500
RPM), it may take many flashes to extend the IAC
valve before engine speed will begin to drop. This
is normal on certain engines. Fully extending the
IAC may cause engine stall. This may be normal.

6E–98
ENGINE DRIVEABILITY AND EMISSIONS
Exhaust Gas Recirculation (EGR) System Check
StepActionVa l u e ( s )Ye sNo
1Check the EGR valve for looseness.
Is the EGR valve Loose?
—Go to Step 2Go to Step 3
2Tighten the EGR valve.
Is the action complete?
—Verify repair—
31. Place the transmission selector in Park or Neutral.
2. Start the engine and idle until warm.
3. Using Tech 2, command EGR “50% ON.”
Does the engine idle rough and lose RPMs?
—
EGR system
working
properly. No
problem
found.
Go to Step 4
41. Engine “OFF.”
2. Ignition “ON.”
3. Using a test light to ground, check the EGR harness
between the EGR valve and the ignition feed.
Does the test light illuminate?
—Go to Step 6Go to Step 5
5Repair the EGR harness ignition feed.
Was the problem corrected?
—Verify repairGo to Step 6
61. Remove the EGR valve.
2. Visually and physically inspect the EGR valve
pintle, valve passages and adapter for excessive
deposits, obstructions or any restrictions.
Does the EGR valve have excessive deposits,
obstructions or any restrictions?
—Go to Step 7Go to Step 8
7Clean or replace EGR system components as
necessary.
Was the problem corrected?
—Verify repairGo to Step 8
81. Ground the EGR valve metal case to battery (–).
2. Using Tech 2, command EGR “ON” and observe the
EGR valve pintle for movement.
Does the EGR valve pintle move according to
command?
—Go to Step 9
Go to DTC
P1406 chart
91. Remove the EGR inlet and outlet pipes from the
intake and exhaust manifolds.
2. Visually and physically inspect manifold EGR ports
and EGR inlet and outlet pipes for blockage or
restriction caused by excessive deposits or other
damage.
Do the manifold EGR ports or inlet and outlet pipes
have excessive deposits, obstructions, or any
restrictions?
—Go to Step 10
EGR system
working
properly. No
problem
found.
10Clean or replace EGR system components as
necessary.
Is the action complete?
—Verify repair—