The Engine Cranks but Does Not Run diagnostic table assumes that battery condition and engine cranking speed are OK. If the battery condition and the cranking speed are not OK, refer to Engine Electrical for diagnosis. Make sure that there is adequate fuel in the tank(s).
• | 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 PCM will default to the speed density (MAP, IAT, RPM) 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 .
The numbers below refer to the step numbers on the diagnostic table.
This step checks the IGN mini relay for proper operation. The IGN mini relay supplies voltage to the injectors and the ignition coils. When the IGN mini relay is not operating properly, a no start condition occurs. If the test lamp does not illuminate, this indicates the IGN mini relay is not suppling a voltage to the fuses. Refer to Ignition Relay Diagnosis for further diagnosis.
This step is checking for a grounded ignition feed circuit for the crankshaft position sensor and the camshaft position sensor. When the ignition feed circuit is shorted, a no start occurs and no DTCs are set. The ignition feed circuits are connected internally within the PCM. The PCM cannot detect the engine is cranking with a grounded ignition feed circuit. If no engine speed is displayed on the scan tool, inspect the ignition feed circuit for a short to ground.
The scan tool may reset if the battery is at a low state of charge. The battery may need to be charged to perform this step.
Refer to full page schematic for complete details of the ignition feed circuit.
Refer to full page schematic for complete details of the ignition feed circuit.
The ignition feed circuits for the Camshaft and Crankshaft Position sensors is internally connected within the PCM. A short to ground on either circuit will cause a no start condition.
The fuel cap may need to be removed to hear the fuel pump running.
Step | Action | Value(s) | Yes | No | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1 | Did you perform the Powertrain On-Board Diagnostic (OBD) System Check? | -- | ||||||||||||
Does the test lamp illuminate on both sides of all the fuses? | -- | Go to Ignition Relay Diagnosis | ||||||||||||
3 | Select the Diagnostic Trouble Code (DTC) option using the scan tool. Does the scan tool display any Throttle Actuator Control (TAC) system DTCs? | -- | Go to the applicable DTC table | |||||||||||
4 |
Important: Check the BCM for DTCs related to Vehicle Theft Deterrent (VTD) system. This indicates a problem with the Column Lock or VTD fuel enable systems. If a BCM DTC is stored, refer to Body and Accessories. Select the Diagnostic Trouble Code (DTC) option using the scan tool. Is P0230, P0335, P0336, P0601, P0602, P0604, or P0606 displayed? | -- | Go to the applicable DTC table | |||||||||||
Monitor the engine speed while cranking the engine. Is engine RPM indicated on the scan tool? | -- | |||||||||||||
Does the DMM display near the specified value? | B+ | |||||||||||||
Does the DMM display near the specified value? | B+ | |||||||||||||
Inspect the Camshaft and Crankshaft Position sensor ignition feed circuits for a short to ground. Did you find and correct the condition? | -- | |||||||||||||
9 | Check the engine coolant temperature using the scan tool. Is the engine coolant temperature on the scan tool close to the actual engine temperature? | -- | Go to DTC P0118 Engine Coolant Temperature (ECT) Sensor Circuit High Voltage | |||||||||||
Enable the fuel pump using the scan tool. Does the fuel pump operate? | -- | |||||||||||||
11 |
Is the fuel pressure within the specified range? | 380-420 kPa (55-61 psi) | Go to Fuel System Diagnosis | |||||||||||
12 | Perform the following additional checks:
Did you find and correct the condition? | -- | Go to Symptoms for diagnosis | |||||||||||
13 | Replace the CKP sensor. Refer to Crankshaft Position Sensor Replacement . Is the action complete? | -- | -- | |||||||||||
14 | Replace the CMP sensor. Refer to Camshaft Position Sensor Replacement . Is the action complete? | -- | -- | |||||||||||
15 |
Important: Program the replacement PCM. Refer to Powertrain Control Module/Throttle Actuator Control Module Replacement . Replace the PCM. Is the action complete? | -- | -- | |||||||||||
16 |
Does the engine start and continue to run? | -- | ||||||||||||
17 |
Are any DTCs displayed? | -- | Go to the applicable DTC table | |||||||||||
18 | Select the Capture Info option and the Review Info option using the scan tool. Are any DTCs displayed that you have not diagnosed? | -- | Go to the applicable DTC table | System OK |