Checks
| Action
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Definition: The engine cranks normally, but does not start in a normal
amount of time. The engine does eventually run, or may start but immediately
stalls.
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Preliminary Checks
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| • | Make sure the vehicle's operator is using the correct starting
procedure. |
|
Sensor Checks
|
| • | Check the Engine Coolant Temperature (ECT) sensor with the scan
tool. Compare the engine coolant temperature with the ambient air temperature
on a cold engine. If the coolant temperature reading is more than 5 degrees
greater or less than the ambient air temperature on a cold engine, check
for a high resistance in the coolant sensor circuit. |
| • | Check the Throttle Position (TP) sensor. If a sticking throttle
shaft or binding linkage causes a high TP sensor voltage (open throttle indication),
the Control Module will not control the idle. While monitoring the TP sensor
voltage, the scan tool should display less than 0.85 volt with the
throttle closed. |
|
Fuel System Checks
|
| | Important: A faulty in-tank fuel pump check valve will allow the fuel in the lines
to drain back to the tank after the engine stops.
|
| • | Check for water contamination in the fuel. |
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Ignition System Checks
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- Check for the proper ignition voltage output with J 26792
or the equivalent.
- Check the spark plugs for the following conditions:
- Check for bare or shorted ignition wires.
- Check for moisture in the distributor cap if applicable.
- Check for loose ignition coil connections.
- Check for loose Ignition Control Module connections.
- Check for a faulty Control Module or ignition system grounds.
- Check the Ignition Control (IC) circuit for an open or short to
ground Refer to
Enhanced Ignition System Diagnosis
.
|
Engine Mechanical Checks
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| • | Check for the following: |
| - | Broken or weak valve springs |
| - | Worn camshaft lobes Refer to Engine Mechanical |
| • | Check the intake and exhaust manifolds for casting flash. Refer
to Engine Mechanical. |
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Additional Check
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