
TEST ACTION APPLICABILITY
15 If there are no possible causes remaining, view repair. All
Repair
Replace the Fuel Pump Module.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
16NOTE: Check for contaminates that may have damaged the O2 Sensor:
contaminated fuel, unapproved silicone, oil and coolant.
WARNING: WHEN THE ENGINE IS OPERATING, DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR HANDS NEAR THE
PULLEYS, BELTS OR FAN. DO NOT WEAR LOOSE CLOTHING.
NOTE: The conditions that set the DTC are not present at this time. The
following list may help in identifying the intermittent condition.
With the engine running at normal operating temperature, monitor the DRB
parameters related to the DTC while wiggling the wiring harness. Look for param-
eter values to change and/or a DTC to set.
Review the DRB Freeze Frame information. If possible, try to duplicate the
conditions under which the DTC was set.
Refer to any Technical Service Bulletins (TSB) that may apply.
Visually inspect the related wiring harness. Look for any chafed, pierced, pinched, or
partially broken wires.
Visually inspect the related wiring harness connectors. Look for broken, bent, pushed
out, or corroded terminals.
Were any of the above conditions present?All
Ye s®Repair as necessary
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Test Complete.
94
DRIVEABILITY - GAS
P0171-1/1 FUEL SYSTEM LEAN ÐContinued

Symptom:
P0172-1/1 FUEL SYSTEM RICH
When Monitored and Set Condition:
P0172-1/1 FUEL SYSTEM RICH
When Monitored: With the engine running in closed loop mode, the ambient/battery
temperature above 20 deg. F and altitude below 8000 ft.
Set Condition: If the PCM multiplies short term compensation by long term adaptive and
the result is below a certain value for two trips, a freeze frame is stored, the MIL
illuminates and a trouble code is stored.
POSSIBLE CAUSES
INTERMITTENT CONDITION
O2 SENSOR HEATER OPERATION
O2 SENSOR
EVAP PURGE SOLENOID OPERATION
O2 SENSOR SIGNAL CIRCUIT SHORTED TO VOLTAGE
O2 SENSOR SIGNAL CIRCUIT OPEN
TPS VOLTAGE GREATER THAN 0.92 VOLTS WITH THROTTLE CLOSED
TP SENSOR SWEEP
MAP SENSOR OPERATION
ECT SENSOR OPERATION
ENGINE MECHANICAL PROBLEM
FUEL FILTER/PRESSURE REGULATOR (HIGH)
PCM
TEST ACTION APPLICABILITY
1NOTE: Check for contaminates that may have damaged the O2 Sensor:
contaminated fuel, unapproved silicone, oil and coolant.
Turn the ignition on.
With the DRBIIIt, read DTC's.
Is the Good Trip displayed and equal to zero?All
Ye s®Go To 2
No®Go To 15
95
DRIVEABILITY - GAS

TEST ACTION APPLICABILITY
6 Turn the ignition on.
With the DRBIIIt, read TP Sensor voltage.
NOTE: The throttle must be against the stop.
Is the voltage 0.92 or less with the Throttle closed?All
Ye s®Go To 7
No®Check for a binding throttle condition. If OK, replace the Throttle
Position Sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
7 Turn the ignition on.
With the DRBIIIt, read the TP Sensor voltage.
While monitoring the DRBIIIt, slowly open and close the throttle.
Does the voltage increase and decease smoothly?All
Ye s®Go To 8
No®Replace the Throttle Position Sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
8 Turn the ignition off.
Connect a Vacuum Gauge to a Manifold Vacuum source.
Start the engine.
Allow the engine to idle.
Note: If engine will not idle, maintain a constant RPM above idle.
With the DRBIIItin Sensors, read the MAP Sensor vacuum value.
Is the DRB reading within 19of the Vacuum Gauge reading?All
Ye s®Go To 9
No®Replace the MAP Sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
9Note: For this test to be valid, the thermostat must be operating correctly.
Note: This test works best if performed on a cold engine (cold soak)
Turn the ignition on.
With the DRBIIIt, read the Engine Coolant Temperature Sensor value. If the engine
was allowed to sit overnight (cold soak), the temperature value should be a sensible
value that is somewhere close to the ambient temperature.
Note: If engine coolant temperature is above 82ÉC (180ÉF), allow the engine
to cool until 65ÉC (150ÉF) is reached.
Start the Engine.
During engine warm-up, monitor the Engine Coolant Temperature value. The temp
value change should be a smooth transition from start up to normal operating temp
82ÉC (180ÉF). The value should reach at least 82ÉC (180ÉF).
Did the Engine Coolant Temperature value increase a smooth transition and did it
reach at least 82ÉCAll
Ye s®Go To 10
No®Replace the Engine Coolant Temperature Sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
97
DRIVEABILITY - GAS
P0172-1/1 FUEL SYSTEM RICH ÐContinued

TEST ACTION APPLICABILITY
15NOTE: Check for contaminates that may have damaged the O2 Sensor:
contaminated fuel, unapproved silicone, oil and coolant.
WARNING: WHEN THE ENGINE IS OPERATING, DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR HANDS NEAR THE
PULLEYS, BELTS OR FAN. DO NOT WEAR LOOSE CLOTHING.
NOTE: The conditions that set the DTC are not present at this time. The
following list may help in identifying the intermittent condition.
With the engine running at normal operating temperature, monitor the DRB
parameters related to the DTC while wiggling the wiring harness. Look for param-
eter values to change and/or a DTC to set.
Review the DRB Freeze Frame information. If possible, try to duplicate the
conditions under which the DTC was set.
Refer to any Technical Service Bulletins (TSB) that may apply.
Visually inspect the related wiring harness. Look for any chafed, pierced, pinched, or
partially broken wires.
Visually inspect the related wiring harness connectors. Look for broken, bent, pushed
out, or corroded terminals.
Were any of the above conditions present?All
Ye s®Repair as necessary
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Test Complete.
99
DRIVEABILITY - GAS
P0172-1/1 FUEL SYSTEM RICH ÐContinued

Symptom List:
P0442-EVAP LEAK MONITOR MEDIUM (.040) LEAK DETECTED
P0455-EVAP LEAK MONITOR LARGE LEAK DETECTED
P0456 - EVAP LEAK MONITOR SMALL LEAK DETECTED
Test Note: All symptoms listed above are diagnosed using the same tests.
The title for the tests will be P0442-EVAP LEAK MONITOR
MEDIUM (.040) LEAK DETECTED.
When Monitored and Set Condition:
P0442-EVAP LEAK MONITOR MEDIUM (.040) LEAK DETECTED
When Monitored: Immediately after a cold start, with battery/ambient temperature
between 4ÉC (40ÉF) and 32ÉC (90ÉF) and coolant temperature within -12ÉC (10ÉF) of
battery/ambient.
Set Condition: If there is a leak larger than 0.0409and smaller than 0.0809in the
evaporative system.
P0455-EVAP LEAK MONITOR LARGE LEAK DETECTED
When Monitored: Immediately after a cold start, with battery/ambient temperature
between 4ÉC (40ÉF) and 32ÉC (90ÉF) and coolant temperature within -12ÉC (10ÉF) of
battery/ambient.
Set Condition: There is a leak larger than 0.0809in the evaporative system.
P0456 - EVAP LEAK MONITOR SMALL LEAK DETECTED
When Monitored: Immediately after a cold start, with battery/ambient temperature
between 4ÉC (40ÉF) and 30ÉC (86ÉF) and coolant temperature within -12ÉC (10ÉF) of
battery/ambient.
Set Condition: If there is a leak larger than 0.0209and smaller than 0.0409in the
evaporative system.
POSSIBLE CAUSES
CONFIRMED LEAK IN THE EVAP SYSTEM
INTERMITTENT LDP MONITOR FAILURE
136
DRIVEABILITY - GAS

Symptom:
P1195-1/1 O2 SENSOR SLOW DURING CATALYST MONITOR
When Monitored and Set Condition:
P1195-1/1 O2 SENSOR SLOW DURING CATALYST MONITOR
When Monitored: With the engine running, coolant greater than 70ÉC (158ÉF), open
throttle, steady to slightly increasing vehicle speed greater than 18 mph but less than 55
mph, with a light load on the engine, for a period no less than 5 minutes.
Set Condition: The oxygen sensor signal voltage is switching from below 0.39 volt to
above 0.6 volts and back fewer times than required.
POSSIBLE CAUSES
INTERMITTENT CONDITION
EXHAUST LEAK
O2 SENSOR SIGNAL CIRCUIT VOLTAGE DROP
O2 SENSOR GROUND CIRCUIT VOLTAGE DROP
O2 SENSOR
TEST ACTION APPLICABILITY
1NOTE: Check for contaminates that may have damaged the O2 Sensor:
contaminated fuel, unapproved silicone, oil and coolant.
Turn the ignition on.
With the DRBIIIt, read DTC's.
Is the Good Trip displayed and equal to zero?All
Ye s®Go To 2
No®Go To 6
2 Start the engine.
Inspect the exhaust for leak between the engine and the O2 sensor.
Inspect the exhaust for leaks between the engine and the appropriate rear O2 Sensor.
Are there any exhaust leaks?All
Ye s®Repair or replace the leaking exhaust parts as necessary.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Go To 3
178
DRIVEABILITY - GAS

TEST ACTION APPLICABILITY
3NOTE: Ensure the voltmeter leads meet the terminals in the connector and
that there is good terminal to wire connection.
NOTE: Ensure the voltmeter leads are connected for positive polarity
Backprobe between the O2 Sensor Signal circuit at the O2 Sensor harness connector
and PCM harness connector.
Start the engine.
Allow the engine to idle.
Is the voltage below 0.10 volt?All
Ye s®Go To 4
No®Repair the high resistance on the O2 Sensor Signal circuit.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
4NOTE: Ensure the voltmeter leads meet the terminals in the connector and
that there is good terminal to wire connection.
NOTE: Ensure the voltmeter leads are connected for positive polarity
Backprobe between the O2 Sensor ground circuit at the O2 Sensor harness connector
and PCM harness connector.
Start the engine.
Allow the engine to idle.
Is the voltage below 0.10 volt?All
Ye s®Go To 5
No®Repair the high resistance on the O2 Sensor ground circuit.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
5 If there are no possible causes remaining, view repair. All
Repair
Replace the O2 Sensor
Perform POWERTRAIN VERIFICATION TEST VER - 5.
6NOTE: Check for contaminates that may have damaged the O2 Sensor:
contaminated fuel, unapproved silicone, oil and coolant.
WARNING: WHEN THE ENGINE IS OPERATING, DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR HANDS NEAR THE
PULLEYS, BELTS OR FAN. DO NOT WEAR LOOSE CLOTHING.
NOTE: The conditions that set the DTC are not present at this time. The
following list may help in identifying the intermittent condition.
With the engine running at normal operating temperature, monitor the DRB
parameters related to the DTC while wiggling the wiring harness. Look for param-
eter values to change and/or a DTC to set.
Review the DRB Freeze Frame information. If possible, try to duplicate the
conditions under which the DTC was set.
Refer to any Technical Service Bulletins (TSB) that may apply.
Visually inspect the related wiring harness. Look for any chafed, pierced, pinched, or
partially broken wires.
Visually inspect the related wiring harness connectors. Look for broken, bent, pushed
out, or corroded terminals.
Were any of the above conditions present?All
Ye s®Repair as necessary
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Test Complete.
179
DRIVEABILITY - GAS
P1195-1/1 O2 SENSOR SLOW DURING CATALYST MONITOR ÐContinued

Symptom:
P1281-ENGINE IS COLD TOO LONG
When Monitored and Set Condition:
P1281-ENGINE IS COLD TOO LONG
When Monitored: The ignition key on, engine running.
Set Condition: The engine does not warm to 71ÉC (160ÉF) while driving (throttle off idle)
greater than 20 MPH for 20 minutes after start.
POSSIBLE CAUSES
COOLING SYSTEM PROBLEM
TEST ACTION APPLICABILITY
1NOTE: The best way to diagnose this DTC is to allow the vehicle to remain
outside overnight in order to have a completely cold soaked engine.
NOTE: Extremely cold outside ambient temperatures may cause this DTC to
set.
Verify that the coolant level is correct. If not, repair as necessary
NOTE: Ensure the ECT Sensor is operating correctly.
With the DRBIIIt, monitor the Engine Coolant Temperature value during the warm
up cycle. Make sure the transition of the temperature change is smooth.
Did the engine temperature reach a minimum of 71ÉC (160ÉF)?All
Ye s®Test Complete.
No®Refer to the Service Information for cooling system performance
diagnosis. The most probable cause is a Thermostat problem.
Also, refer to any related TSBs.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
180
DRIVEABILITY - GAS