Checks
| Action
|
DEFINITION: Momentary
lack of response as the accelerator is pushed down. Can occur at any vehicle
speed. Usually more pronounced when first trying to make the vehicle move,
as from a stop sign. May cause the engine to stall if severe enough.
|
Preliminary
|
| • | Check PCM grounds for being clean, tight and in their proper locations. |
|
Sensor/System
|
| • | Check MAP sensor operation. |
| • | Check EGR for being loose or for a faulty gasket. Check EGR operation
for flow all the time. |
| • | Using a Scan Tool, monitor TP sensor voltage. The TP sensor voltage
should be less then 0.9 volt at rest. Also inspect throttle body and accelerator
cables for binding. |
|
Fuel System
|
| • | Check for restricted fuel filter. |
| • | Check injector fuse(s) for being open. An open injector fuse will
cause the injectors not to operate. Replace fuse and inspect injector circuits
for an intermittent short to ground. |
| • | Perform injector balance test. |
| • | Check items which can cause an engine to run rich (long term fuel
trim near -99%). |
| • | Check items that can cause an engine to run lean (long term fuel
trim near 100%). |
|
Ignition System
|
| • | Wetting down the secondary ignition system with water from a spray
bottle may help locate damaged or deteriorated components. Look/listen for
arcing or misfiring as water is applied. |
| • | Remove spark plugs and check for the following: |
| • | An improper spark plug gap will cause a driveability problem.
The spark plug gapping should be done using a wire gauge gap tool (J 41319). |
| • | If spark plugs are gas or oil fouled, the cause of the fouling
must be determined before replacing the spark plugs. |
| • | Check for loose ignition control module ground. |
| • | Spark plugs for proper heat range. Refer to the owner's manual
to determine the proper replacement spark plugs. |
|
Engine Cooling System
| Check the engine thermostat for functioning correctly and
for proper heat range. Refer to
Thermostat Diagnosis
in Engine Cooling.
|
Additional Checks
| Check generator output voltage.
Refer to
Generator Usage
in Engine Electrical.
|
