| DEFINITION: Engine cranks OK, but does not start for a long time. Does eventually run, or may start but immediately dies. |
| Preliminary |
|
| Sensor/System |
- Verify that the engine coolant temperature (ECT) sensor is not shifted in value. Refer to Temperature vs Resistance
for resistance specifications.
- Verify proper operation of the manifold absolute pressure (MAP) sensor. Refer to Scan Tool Data Definitions
.
|
| Fuel System |
|
| Ignition System |
- Inspect for proper ignition voltage output with the J 26792
Spark Tester. See Special Tools
. Refer to Electronic Ignition (EI) System Diagnosis .
- Remove the spark plugs and inspect for the following conditions:
- Determine the cause of the conditions before replacing the spark plugs.
- Inspect for loose ignition coil grounds.
- Inspect the ignition coils for cracks or carbon tracking.
- Soak the secondary ignition with water may help locate an intermittent problem. Ignition voltage will arc to ground when a secondary component is faulty.
|
| Engine Mechanical |
Inspect for the following conditions:
- Excessive oil in combustion chamber or leaking valve seals-Refer Oil Consumption Diagnosis
in Engine Mechanical.
- Cylinder compression-Refer to Engine Compression Test
in Engine Mechanical.
- Improper valve timing
- Worn rocker arms
- Broken or worn valve springs
- Combustion chambers for excessive carbon buildup-Clean the chambers using top engine cleaner. Follow the instructions on the can.
- Incorrect or damaged basic engine parts-Inspect the following components:
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 Bearings Cleaning and Inspection
in Engine Mechanical. This could result in any of the following conditions:
- A no start
- A start and stall
- Erratic performance
|
| Additional |
- Inspect for a restricted exhaust. Refer to Restricted Exhaust
in Engine Exhaust.
- Inspect the air intake ducts for being collapsed, damaged, loose, improperly installed, or leaking, especially between the mass air flow (MAF) sensor and the throttle body.
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