Engine Cranks But Does Not Run
Diagnostic Chart (Part 1 Of 2):
Diagnostic Chart (Part 2 Of 2):
Schematic:
DESCRIPTION
The Engine Cranks but Does Not Run diagnostic table assumes that the battery condition and the engine cranking speed are OK. If the battery condition and the cranking speed are not OK, refer to A Diagnostic System Check - Starting and Charging in Starting and Charging for diagnosis. Make sure that there is adequate fuel in the fuel tanks. Testing and Inspection
DIAGNOSTIC AIDS
^ Check the duct work between the Mass Air Flow (MAF) sensor and the throttle body for air leaks.
^ A malfunctioning MAF sensor may cause a no start or a stall after start. If you suspect this, disconnect the MAF sensor. The Powertrain Control Module (PCM) will default to the speed density in order to calculate the load and the air flow. If this corrects the condition and the connections are OK, replace the MAF sensor.
If the steps above check OK, refer to Symptoms. Symptom Related Diagnostic Procedures
TEST DESCRIPTION
The numbers below refer to the step numbers on the diagnostic table.
4. It may be necessary to connect a battery charger to the battery for this step. If the battery state of charge is low, the scan tool may reset during the cranking test.
5. This step tests the ignition relay for proper operation. The ignition relay supplies voltage to the injectors and the ignition coils. When the ignition relay is not operating properly, a no start condition occurs. If the test lamp does not illuminate, this indicates the ignition relay is not supplying a voltage to the fuses.
6. The Crankshaft Position (CKP) sensor is located above the starter.
7. The Camshaft Position (CMP) sensor is located at the rear of the engine behind the intake manifold.
8. The ignition feed circuit for the CMP and CKP sensors is internally connected within the PCM. A short to ground on either circuit will cause a no start condition.
10. The fuel cap may need to be removed in order to hear if the fuel pump is operating.
12. At this point the engine should start. Refer to Hard Start for further diagnosis. Hard Start