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 the PCM grounds for being clean, tight and in their proper
locations. Refer to
Wiring Repairs
in Wiring Systems. |
|
Sensor/System
|
| • | Check the Engine Coolant Temperature (ECT) sensor for being shifted
in value. Connect a scan tool. Compare the Engine Coolant Temperature against
the Intake Air Temperature (IAT) on a cold engine. The ECT and IAT sensor
values should be within ± 3°C (5°F) of each other. If
the ECT sensor is out of range with the IAT sensor, check the resistance
of the ECT sensor. Refer to Temperature vs Resistance
for resistance specifications. Replace the 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 the Mass Air Flow sensor installation. A MAF sensor that
is incorrectly installed may cause a hard start. Important: The embossed arrows
on the MAF sensor indicate the direction of the intake air flow. The
arrows must point toward the engine. Install the MAF in the proper direction.
Refer to
Mass Airflow Sensor Replacement
. |
|
Fuel
System
|
| • | A faulty in-tank fuel pump check valve allows the fuel in
the lines to drain back to the tank after the engine stops. To check for this
condition, refer to
Fuel System Diagnosis
. |
| • | Check both injector fuses for being open. An open injector fuse
causes four injectors and four ignition coils not to operate. Replace the
fuse. Inspect the injector circuits and the ignition coil circuits for
an intermittent short to ground. |
|
Ignition
System
|
| • | Check both injector fuses for being open. An open injector fuse
causes four ignition coils and four injectors not to operate. Replace the
fuse. Inspect the ignition coil circuits and the injector circuits for
an intermittent short to ground. |
| • | Remove the spark plugs and check for the following: |
| • | Determine the cause of the fouling before replacing the spark
plugs if the spark plugs are gas or oil fouled. |
| • | Check the spark plugs for proper heat range. Refer to
Maintenance Items
in Maintenance and Lubrication. |
| • | Check for improper resistance or faulty connections at the Crankshaft
Position (CKP) Sensor. Refer to Electronic Ignition System check. |
|
Engine
Mechanical
|
| • | Excessive oil in combustion chamber-Leaking valve seals.
Refer to Oil Consumption Diagnosis
in Engine Mechanical. |
| • | Combustion chambers for excessive carbon buildup. Clean the chambers
using Top engine cleaner. Follow the instructions on the can. |
| • | For incorrect basic engine parts. Inspect the following: |
Refer to Engine Mechanical.
|
