Inspection/Tests
| Action
|
DEFINITION: Engine delivers less than expected power. Little or no increase in speed when the accelerator pedal is pushed down part way.
|
Preliminary Inspections
|
|
Fuel System
|
• | Inspect for the following that may cause the engine to run rich: |
Notice: Refer to Heated Oxygen and Oxygen Sensor Notice in the Preface section. - | Water intrusion in the heated oxygen sensor (HO2S) connector |
- | Purging of a saturated evaporative emission (EVAP) canister |
- | Vacuum hoses that are split, kinked, or improperly connected |
• | Inspect for the following conditions that may cause the engine to run lean: |
Notice: Refer to Heated Oxygen and Oxygen Sensor Notice in the Preface section. - | Water intrusion in the HO2S connector |
- | An exhaust leak between the HO2S and the engine--Refer to
Exhaust Leakage
. |
- | Vacuum hoses that are split, kinked, or improperly connected |
|
Sensor/System
| Monitor the knock sensor (KS) system for excessive spark retard activity with a scan tool. Refer to
Scan Tool Data List
.
|
Ignition System
|
• | In order to properly inspect the spark plugs or to correct a condition, refer to the following procedures: |
• | Inspect for proper secondary ignition voltage output with
J 26792
HEI Spark Tester. |
• | An improper spark plug gap will cause a driveability condition. Gap the spark plugs using a wire gage gap tool. |
• | If the spark plugs are found to be fouled, determine the cause before replacing the spark plugs. |
• | Monitor the Misfire Current Counters while driving the vehicle in the conditions that the symptom occurred. If a misfiring cylinder can be located, use the DTC P0300 table for diagnosis. Refer to
DTC P0300
. |
• | Soak the secondary ignition system with water from a spray bottle. Soaking the secondary ignition system may help locate damaged or deteriorated components. Look and listen for arcing or misfiring as you apply the water. |
|
Engine Mechanical
|
• | Inspect for incorrect camshaft timing. |
• | Inspect for incorrect, worn, or damaged basic engine parts, including the following: |
• | Inspect for excessive crankshaft endplay that will cause the crankshaft position (CKP) sensor reluctor wheel to move out of alignment with the CKP sensor. Refer to
Crankshaft and Bearing Cleaning and Inspection
. This could result in any of the following conditions: |
|
Additional Inspections
|
• | Inspect the exhaust system for damaged or collapsed pipes. |
• | Inspect the mufflers for heat distress or internal failure. |
|