Engine Cranks But Does Not Run. Pontiac Firebird 2000

For 1990-2009 cars only

Makes 🢒 Pontiac 🢒 2000 🢒 Firebird 🢒 Transmission/Transaxle 🢒 Automatic Transmission - 4L60-E 🢒 Engine Cranks But Does Not Run

Description

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 Diagnostic System Check - Engine Electrical in Engine Electrical for diagnosis. Make sure that there is adequate fuel in the tank.

Diagnostic Aids

•	The following may cause an intermittent:

-	Poor connections--refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Corrosion

-	Mis-routed harness

-	Rubbed through wire insulation

-	Broken wire inside the insulation

•	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. Refer to Mass Airflow Sensor Replacement for procedures.

•	If certain components are disconnected at the same time, the engine may not start and NO DTCs set.

•	For an intermittent, refer to Symptoms .

Test Description

The numbers below refer to the step numbers on the diagnostic table.

Certain DTCs only set while cranking the engine. This step verifies if a component is causing the no start condition.

This step is testing 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 that 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.

This step verifies the IGN relay for proper operation. The IGN relay supplies voltage to the injectors and the ignition coils. When the IGN relay is not operating properly, a no start condition occurs. If the test lamp does not illuminate, this indicates the IGN relay is not suppling a voltage to the fuses.

The Crankshaft Position sensor is located near the starter.

The Camshaft Position sensor is located at the rear of the engine behind the intake manifold.

The ignition feed circuit for the Camshaft and Crankshaft Position sensors is internally connected within the PCM. A short to ground on either circuit causes a no start condition.

The fuel cap may need to be removed to hear if the fuel pump is operating.

Step

Action

Value(s)

Yes

Did you perform the Powertrain On-Board Diagnostic (OBD) System Check?

Go to Step 2

Go to Powertrain On Board Diagnostic (OBD) System Check

Important: Refer to applicable DTC table if any of the following DTCs are set: P0230, P0335, P0336, P0601, P0602, P0604.

Crank the engine for the specified amount of time.

Does the scan tool display any DTCs that failed this ignition?

15 seconds

Go to the applicable DTC table

Go to Step 3

Monitor the VTD Fuel Enabled status using a scan tool.

Does the scan tool display Active?

Go to DTC P1626 Theft Deterrent Fuel Enable Signal Lost

Go to Step 4

Monitor the engine speed while cranking the engine.

Is engine RPM indicated on the scan tool?

Go to Step 5

Go to Step 6

Turn ON the ignition leaving the engine OFF.
Probe both sides of the fuses (located in the Underhood Electrical Center 2) listed below using the J 35616-200 test lamp connected to ground.

•

INJR1

•

INJR2

•

ENG CTRL

•

ENG SEN

•	A/C CRUISE

Does the test lamp illuminate on both sides of all the fuses?

Go to Step 9

Go to Ignition Relay Diagnosis

Disconnect the Crankshaft Position (CKP) sensor electrical connector. Refer to Crankshaft Position Sensor Replacement .
Measure the voltage at the ignition feed circuit at the CKP electrical connector using the DMM.

Does the DMM display near the specified value?

B+

Go to Step 13

Go to Step 7

Disconnect the Camshaft Position (CMP) sensor electrical connector. Refer to Camshaft Position Sensor Replacement .
Measure the voltage at the ignition feed circuit at the CMP electrical connector using the DMM.

Does the DMM display near the specified value?

B+

Go to Step 14

Go to Step 8

Test the Camshaft and Crankshaft Position sensor ignition feed circuits for a short to ground. Refer to Testing for Short to Ground in Wiring Systems.
If you find a grounded circuit repair the circuit as necessary. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 16

Go to Step 15

Monitor 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 Step 10

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?

Go to Step 11

Go to Fuel Pump Electrical Circuit Diagnosis

Turn OFF the ignition.
Install a fuel pressure gauge. Refer to Fuel System Diagnosis .
Turn ON the ignition leaving the engine OFF.
Observe the fuel pressure.

Is the fuel pressure within the specified range when the fuel pump is operating?

380-420 kPa (55-61 psi)

Go to Step 12

Go to Fuel System Diagnosis

Perform the following additional inspections:

•	Inspect the duct work between the Mass Air Flow (MAF) sensor and the throttle body for air leaks.

•	Inspect that the throttle angle is at 0% at a closed throttle. If the throttle angle is not at 0%, refer to DTC P0122 Throttle Position (TP) Sensor Circuit Low Voltage and DTC P0123 Throttle Position (TP) Sensor Circuit High Voltage .

•

A malfunctioning MAF sensor may cause a no start or a stall after a 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 engine load and the intake air flow. If disconnecting the MAF sensor corrects the condition and the connections are OK, replace the MAF sensor. Refer to Mass Airflow Sensor Replacement .

•	Inspect the spark plugs for being gas fouled. Refer to Spark Plug Visual Diagnosis in Engine Electrical. If the spark plugs are gas fouled, determine what caused the rich condition.