Checks
| Action
|
DEFINITION: Engine
cranks OK, but does not start for a long time. Does eventually run, or may
start but immediately dies.
|
Preliminary
|
| • | Refer to Symptoms
, Important Preliminary
Checks Before Starting. |
| • | Check PCM grounds for being clean, tight and in their proper locations. |
|
Sensor/System
|
| • | Check Engine Coolant Temperature (ECT) sensor for being shifted
in value. Connect a Scan Tool and compare Engine Coolant Temperature with
Intake Air Temperature on a cold engine. The ECT and IAT should be within
± 3°C (5°F) of each other. Check the resistance of the ECT
sensor if the temperature is out of range with the IAT sensor. Refer to Temperature vs Resistance
for resistance
specifications. Replace ECT sensor if the resistance is not within the
specification. If the sensor is within the specification, repair ECT signal
circuit for high resistance. |
| • | Check Mass Air Flow sensor installation. |
| • | Using a Scan Tool, monitor TP sensor voltage. The TP sensor voltage
should be less then 0.9 volts at rest. If the TP sensor voltage is greater
than 0.9 volt, inspect the throttle body and accelerator cables for binding. |
| • | Check the EGR system for proper operation. |
|
Fuel System
|
| • | Check fuel pump relay operation -- pump should turn ON for
2 seconds when ignition is turned ON. |
| • | A faulty in-tank fuel pump check valve will allow the fuel in
the lines to drain back to the tank after engine is stopped. To check for
this condition, refer to the Fuel System Pressure Test
. |
| • | Check both injector fuses for being open. An open injector fuse
will cause four injectors not to operate. Replace fuse and inspect injector
circuits for an intermittent short to ground. |
| • | Check for low fuel pressure. |
| • | Check for restricted fuel filter. |
| • | Check for contaminated fuel. Refer to Fuel
Quality Diagnosis.
|
|
Ignition System
|
| • | Check for proper ignition voltage output with spark tester J 26792. |
| • | Remove spark plugs and check for the following: |
If spark plugs are gas or oil fouled, the cause of the fouling must
be determined before replacing the spark plugs.
| • | Check for bare or shorted ignition wires. Refer to Secondary Ignition System Diagnosis
. |
| • | Check for loose Ignition Control module ground. |
| • | Spark plugs for proper heat range. Refer to Owners Manual or General Information.
|
|
Engine Mechanical
|
| • | Excessive oil in combustion chamber-Leaking valve seals.
Refer to Engine Mechanical.
|
| • | Low cylinder compression. Refer to Engine Mechanical.
|
| • | Combustion chambers for excessive carbon buildup. Clean using
Top engine cleaner. Follow instructions on container. |
| • | For incorrect basic engine parts. Inspect the following: |
Refer to Engine Mechanical.
|
Additional Checks
| Using a scan tool, check IAC operation and Typical Scan
Data values.
|
