Checks
| Action
|
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 dies.
|
Preliminary Checks
|
| • | Make sure the vehicle 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 more 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, or an 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 damaged 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. |
|
Ignition
System Checks
|
| • | Check for the proper ignition voltage output with J 26792
Spark Tester 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. |
|
Engine
Mechanical Checks
|
| • | Check for the following: |
| - | Broken or weak valve springs |
| • | Check the intake and exhaust manifolds for casting flash. |
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Additional
Check
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