Checks
| Action
|
DEFINITION: Engine delivers less than expected power. Little
or no increase in speed when the accelerator pedal is pushed down part
way.
|
Preliminary Checks
|
| • | Search for service bulletins. |
| • | Check and compare the customers vehicle to a similar vehicle.
Make sure the customers vehicle has an actual problem. |
| • | Check the air cleaner filter for dirt or restrictions. |
|
Fuel System Checks
|
| • | Check items which can cause an engine to run rich--Long Term
FT is significantly in the negative range. Refer to Diagnostic Aids for
DTC P0172
. |
| • | Check items that can cause an engine to run lean--Long Term
FT is significantly in the positive range. Refer to Diagnostic Aids for
DTC P0171
. |
|
Sensor/System
|
| • | Using a scan tool, monitor KS system for excessive spark retard
activity. Refer to
DTC P0325
. |
| • | Check for proper operation of the MAP sensor. |
| • | Check for proper operation of the TP sensor. |
| • | Check for a restricted air intake system. |
|
Ignition System
|
| • | Check for proper ignition voltage output with the J 26792
. |
| • | Check the spark plugs for the following conditions: |
| - | Improper spark plug gap |
| - | Burned electrodes or heavy deposits |
| • | If the spark plugs are fuel or oil fouled, the cause of the fouling
must be determined before replacing the spark plugs. |
| • | Check the ignition control module (ICM) for proper ground connection. |
| • | Check the ignition coils for cracks or carbon tracking. |
| • | Check the spark plug wires for proper resistance and condition. |
|
Engine Mechanical
|
| • | Check the engine for the following engine mechanical problems: |
| - | Leaking cylinder head gasket |
| - | Worn or a incorrect camshaft |
| • | Refer to the appropriate diagnostic procedures in Engine Mechanical. |
|
Additional Checks
|
| • | Check for proper operation of the torque converter clutch (TCC).
Refer to Automatic Transmission Diagnosis. |
| • | Check the exhaust system for a possible restriction: |
| - | The exhaust system for damaged or for possible collapsed pipes |
| - | The muffler for heat distress or for possible internal failure |
| - | Possible plugged three-way catalytic converter--Refer to Restricted Exhaust System Check
. |
| • | Check the generator output voltage. Repair the generator if the
output voltage is less than 11 volts or more than 16 volts. |
| • | Check the A/C system operation. The A/C clutch should cut out
at the wide open throttle (WOT) position. |
| • | If all procedures have been completed and no malfunctions have
been found, review and inspect the following items: |
| - | All electrical connections within the suspected circuit and/or
systems |
|
