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
|
| • | Verify that the powertrain control module (PCM) grounds are clean,
tight, and in the correct locations. |
|
Sensor and System
|
| • | Inspect the manifold absolute pressure (MAP) sensor operation. |
| • | Inspect for a loose exhaust gas recirculation (EGR) valve and
for a faulty gasket. Inspect for EGR flow all the time. |
| • | Using a scan tool, monitor the throttle position (TP) sensor voltage.
The TP sensor voltage should be less than 0.9 volt at rest. Also inspect
the throttle body and the accelerator cables for binding. |
|
Fuel System
|
| • | Inspect for a restricted fuel filter. |
| • | Inspect for open fuel injector fuses. Replace the fuse if necessary.
Inspect the injector circuits for an intermittent short to ground. |
| • | Perform the fuel injector balance test. |
| • | Inspect the items that can cause an engine to run rich. |
| • | Inspect the items that can cause an engine to run lean. |
|
Ignition System
| Remove the spark plugs. Inspect for the following conditions:
An improper spark plug gap will cause a driveability problem. The spark
plug gapping should be done with a wire gauge gap tool. If the spark plugs
are gas or oil fouled, determine the cause of the fouling before
replacing the spark plugs.
| • | Inspect for a loose ignition control module (ICM) ground. |
| • | Inspect the spark plugs for the correct heat range. |
|
Engine Cooling System
| Inspect the engine thermostat for correct operation and for the correct
heat range. Refer to
Engine Fails To Reach Normal Operating Temperature
in Engine Cooling.
|
Additional Checks
| Inspect the generator
output voltage. Refer to
Diagnostic Starting Point - Engine Electrical
in Engine Electrical .
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