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.
Refer to
PCM wiring diagrams in Electrical Diagnosis.
|
|
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. A MAF sensor that is installed
in the wrong direction, may cause a hard start. Important: Embossed arrows on the
MAF sensor indicate air flow and must point toward the engine. Install MAF in the
proper direction. Refer to
Mass Airflow Sensor Replacement , On-Vehicle Service. |
| • | Using a Scan Tool, monitor TP sensor voltage. The TP sensor voltage should
be less then 0.9 volt. If the TP sensor voltage is greater than 0.9 volt, inspect
the ASR/TCS adjuster assembly (If so equipped). Also inspect throttle body and accelerator
cables for binding. Refer to
Adjuster Assembly Throttle And Cruise
Control Cables.
|
|
Fuel System
|
| • | 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
Fuel System Diagnosis . |
| • | 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. |
|
Ignition System
|
| • | Remove spark plugs and check for the following: |
| • | Refer to
Spark Plug Replacement.
|
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 Ignition Wire Replacement. |
| • | Spark plugs for proper heat range. Refer to
Owners
Manual or Section OB.
|
|
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 can. |
| • | For incorrect basic engine parts. Inspect the following: |
Refer to
Engine Mechanical.
|
Additional Checks
| Using a scan tool, check IAC operation.
|
