3.ENGINE MECHANICAL
Check for any of the following conditions/mechanical problems.
AIR INDUCTION SYSTEM - must be free from leaks
ENGINE VACUUM - must be at least 13 inches in neutral
ENGINE VALVE TIMING - must be within specifications
ENGINE COMPRESSION - must be within specifications
ENGINE EXHAUST SYSTEM - must be free of any restrictions or leaks
ENGINE PCV SYSTEM - must flow freely
TORQUE CONVERTER STALL SPEED - must be within specifications
POWER BRAKE BOOSTER - no internal vacuum leaks
FUEL - must be free of contamination
FUEL INJECTOR - plugged or restricted injector; control wire not connectedtocorrectinjector
Are there any engine mechanical problems?
Ye s>>
Repair as necessary.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 4
4.O2 SENSOR
Ignition on, engine not running.
Disconnect the 1/2 O2 Sensor harness connector.
With the scan tool, monitor the 1/2 O2 Sensor voltage.
The O2 Sensor voltage should read 5.0 volts on the scan tool with the
connector disconnected.
Using a jumper wire, jump the (K141) O2 Sensor 1/2 Signal circuit to
the (K904) O2 Return Downstream circuit in the O2 Sensor harness
connector.
NOTE: The voltage should drop from 5.0 volts to 2.5 volts with the
jumper wire in place.
Did the O2 Sensor volts change from 5.0 volts to 2.5 volts?
Ye s>>
Replace the O2 Sensor
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 5
3.ENGINE MECHANICAL
Check for any of the following conditions/mechanical problems
AIR INDUCTION SYSTEM - must be free from leaks.
ENGINE VACUUM - must be at least 13 inches in neutral
ENGINE VALVE TIMING - must be within specifications
ENGINE COMPRESSION - must be within specifications
ENGINE EXHAUST SYSTEM - must be free of any restrictions or leaks
ENGINE PCV SYSTEM - must flow freely
TORQUE CONVERTER STALL SPEED - must be within specifications
POWER BRAKE BOOSTER - no internal vacuum leaks
FUEL - must be free of contamination
FUEL INJECTOR - plugged or restricted injector; control wire not connectedtocorrectinjector
Are there any engine mechanical problems?
Ye s>>
Repair as necessary.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 4
4.O2 SENSOR
Ignition on, engine not running.
Disconnect the 1/2 O2 Sensor harness connector.
With the scan tool, monitor the 1/2 O2 Sensor voltage.
The O2 Sensor voltage should read 5.0 volts on the scan tool with the
connector disconnected.
Using a jumper wire, jump the (K141) O2 Sensor 1/2 Signal circuit to
the (K904) O2 Return Downstream circuit in the O2 Sensor harness
connector.
NOTE: The voltage should drop from 5.0 volts to 2.5 volts with the
jumper wire in place.
Did the O2 Sensor volts change from 5.0 volts to 2.5 volts?
Ye s>>
Replace the O2 Sensor.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 5
3.ENGINE MECHANICAL
Check for any of the following conditions/mechanical problems.
AIR INDUCTION SYSTEM - must be free from leaks
ENGINE VACUUM - must be at least 13 inches in neutral
ENGINE VALVE TIMING - must be within specifications
ENGINE COMPRESSION - must be within specifications
ENGINE EXHAUST SYSTEM - must be free of any restrictions or leaks
ENGINE PCV SYSTEM - must flow freely
TORQUE CONVERTER STALL SPEED - must be within specifications
POWER BRAKE BOOSTER - no internal vacuum leaks
FUEL - must be free of contamination
FUEL INJECTOR - plugged or restricted injector; control wire not connectedtocorrectinjector
Are there any engine mechanical problems?
Ye s>>
Repair as necessary.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 4
4.O2 SENSOR
Ignition on, engine not running.
Disconnect the 2/2 O2 Sensor harness connector.
With the scan tool, monitor the 2/2 O2 Sensor voltage.
The O2 Sensor voltage should read 5.0 volts on the scan tool with the
connector disconnected.
Using a jumper wire, jump the (K243) O2 Sensor 2/2 Signal circuit to
the (K904) O2 Return Downstream circuit in the O2 Sensor harness
connector.
NOTE: The voltage should drop from 5.0 volts to 2.5 volts with the
jumper wire in place.
Did the O2 Sensor volts change from 5.0 volts to 2.5 volts?
Ye s>>
Replace the O2 Sensor
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 5
3.ENGINE MECHANICAL
Check for any of the following conditions/mechanical problems.
AIR INDUCTION SYSTEM - must be free from leaks
ENGINE VACUUM - must be at least 13 inches in neutral
ENGINE VALVE TIMING - must be within specifications
ENGINE COMPRESSION - must be within specifications
ENGINE EXHAUST SYSTEM - must be free of any restrictions or leaks
ENGINE PCV SYSTEM - must flow freely
TORQUE CONVERTER STALL SPEED - must be within specifications
POWER BRAKE BOOSTER - no internal vacuum leaks
FUEL - must be free of contamination
FUEL INJECTOR - plugged or restricted injector; control wire not connectedtocorrectinjector
Are there any engine mechanical problems?
Ye s>>
Repair as necessary.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 4
4.O2 SENSOR
Ignition on, engine not running.
Disconnect the 2/2 O2 Sensor harness connector.
With the scan tool, monitor the 2/2 O2 Sensor voltage.
The O2 Sensor voltage should read 5.0 volts on the scan tool with the
connector disconnected.
Using a jumper wire, jump the (K243) O2 Signal 2/2 circuit to the
(K904) O2 Return Downstream circuit in the O2 Sensor harness con-
nector.
NOTE: The voltage should drop from 5.0 volts to 2.5 volts with the
jumper wire in place.
Did the O2 Sensor volts change from 5.0 volts to 2.5 volts?
Ye s>>
Replace the O2 Sensor
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 5
3.SECONDARY INDICATORS PRESENT
Ignition on, engine not running.
With the scan tool, under DTCs & Related Functions, read the Secondary Indicators while cranking the engine.
Are there any Secondary Indicators present while cranking the engine?
Ye s>>
Refer to the Engine Electrical Diagnostics group and perform the tests related to the secondary indicator
that is reported by the scan tool.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 4
4.ENGINE MECHANICAL
Check for any of the following conditions/mechanical problems.
ENGINE VALVE TIMING - must be within specifications, check for broken timing components
ENGINE COMPRESSION - must be within specifications
ENGINE EXHAUST SYSTEM - must be free of any restrictions or leaks.
Are there any engine mechanical problems?
Ye s>>
Repair as necessary.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 5
5.(K342) ASD RELAY OUTPUT CIRCUIT OPEN
Turn the ignition off.
Remove the ASD relay from the IPM.
Disconnect the C3 PCM harness connector.
Verify the ASD Relay is getting voltageontheFusedB+circuitsbefore
continuing.
CAUTION: Do not probe the PCM harness connectors. Probing the
PCM harness connectors will damage the PCM terminals resulting
in poor terminal to pin connection. Install Miller Special Tool #8815
to perform diagnosis.
Measure the resistance of the ASD Relay Output circuit from the ASD
Relay connector to the appropriate terminals of special tool #8815, Igni-
tion coil, and the fuel injectors.
Is the resistance below 5.0 ohms?
Ye s>>
Go To 6
No>>
Repair the open in the (K342)ASD Relay Output circuits.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
4.TP SENSOR NO.1 VOLTAGE GREATER THAN0.92 VOLTS WITH THROTTLE CLOSED
With the scan tool, read Throttle Position Sensor No.1 voltage.
Throttle must be against its stop.
Is the voltage 0.92 or less with the Throttle closed?
Ye s>>
Go To 5
No>>
Check for a binding throttle condition. If OK, replace the Throttle Position Sensor or the Throttle Body
Assemblyona5.7L.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
5.ECT SENSOR OPERATION
NOTE: For this test to be valid, the thermostat must be operating correctly.
NOTE: This test works best if performed on a cold engine (cold soaked).
NOTE: If the vehicle was allowed to sit over night with no engine start, coolant temperature should be near
ambient temperatures.
Ignition on, engine not running.
With the scan tool, read the ECT value.
NOTE: If engine coolant temperature is above 82° C (180° F), allow the engine to cool until 65° C (150° F) is
reached.
Start the engine.
During engine warm-up, monitor the Engine Coolant Temperature value. Thetemperature value change should be a
smooth transition from start up to normal operating temp 82° C (180° F). Thevalue should reach at least 82° C
(180° F).
Did the Engine Temperature value increase smoothly and did it reach at least 82° C (180° F)?
Ye s>>
Go To 6
No>>
Replace the Engine Coolant Temperature Sensor.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
6.OTHER POSSIBLE CAUSES OF START AND STALL CONDITION
The following additional items should be checked as a possible cause for a start and stall condition.
Refer to any Technical Service Bulletins (TSBs) that may apply to the symptom.
The exhaust system must be free of any restrictions.
The engine compression must be within specifications.
The engine valve timing must be within specifications.
Theenginemustbefreefromvacuumleaks.
The throttle body must be free of carbon buildup and dirt.
Do any of the above conditions exist?
Ye s>>
Repair as necessary.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 7
P0300-MULTIPLE CYLINDER MISFIRE
For a complete wiring diagramRefer to Section 8W.
When Monitored:
While the engine is idling.
Set Condition:
Misfire detected on multiple cylinders.
Possible Causes
LOW FUEL
OTHER DTC’S
DAMAGED FUEL LINES
VA LV E T R A I N
OBSTRUCTED FUEL INJECTOR SUPPLY LINES
DAMAGED OR OBSTRUCTED HIGH PRESSURE CONNECTORS
EXTERNAL DAMAGED FUEL INJECTORS
INTERNAL DAMAGED FUEL INJECTOR
NO COMPRESSION
EXCESSIVE ENGINE LEAK DOWN
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)
Diagnostic Test
1.LOW FUEL
Using the scan tool, verify that the fuel level is above 15%.
Is the fuel level above 15%?
Ye s>>
Go To 2
No>>
Addfuelgotostep2.
Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)
2.OTHER DTC’S
Read the Freeze frame data.
Is the DTC equal to the freeze frame DTC?
Ye s>>
Go To 3
No>>
Repair any other DTC’s first.
Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)
8.INTERNAL DAMAGED FUEL INJECTOR
With the scan tool, erase DTCs.
Switch the misfiring injectors & high pressure connectors with injectors& high pressure connectors from cylinders
that are firing properly.
Operate the vehicle.
Did the misfire DTC follow the suspect injectors & high pressure connectors?
Ye s>>
Replace the internal damaged fuel injector and high pressure connector.
Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)
No>>
Go To 9
9.INTERNAL ENGINE DAMAGE
Perform engine compression test
Did the suspect cylinders pass the compression test?
Ye s>>
Go To 10
No>>
Repair the internal damage to the engine.
Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)
10.INTERNAL ENGINE DAMAGE
Perform engine leak down test
Did the suspect cylinders pass the leak down test?
Ye s>>
Te s t C o m p l e t e .
No>>
Repair the internal damage to the engine.
Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)