GM Service Manual Online
For 1990-2009 cars only

Description

The Engine Cranks but Does Not Run diagnostic table is an organized approach to identifying a condition that causes an engine not to start. The Engine Cranks but Does Not Run diagnostic table directs the service technician to the appropriate system diagnosis.

The Engine Cranks but Does Not Run diagnostic table assumes the following:

    • The battery is completely charged. Refer to Battery Inspection/Test in Engine Electrical.
    • The engine cranking speed is acceptable. Refer to Engine Cranks Slowly in Engine Electrical.
    • There is adequate fuel in the fuel tank.

Test Description

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

  1. This step determines if the ignition relay is providing the listed fuses with voltage.

  2. This step determines if the fuel pump is operating electrically.

  3. If all the Cylinder Injector Circuit Status parameters display Fault, this indicates a condition with the injector supply voltage circuit.

Step

Action

Values

Yes

No

1

Did you perform the Diagnostic System Check-Engine Controls?

--

Go to Step 2

Go to Diagnostic System Check - Engine Controls

2

  1. Turn ON the ignition, with the engine OFF.
  2. Observe the DTC information with a scan tool.

Does the scan tool display DTC P0101, P0230, P0601, P0602, P1626, P1630, or P1631?

--

Go to Diagnostic Trouble Code (DTC) List

Go to Step 3

3

  1. Turn ON the ignition, with the engine OFF.
  2. Probe both sides of the following fuses:
  3. • ELEC ENG
    • Fuel INJ

Does the test lamp illuminate on at least one side of the fuses listed?

--

Go to Step 4

Go to Ignition Relay Diagnosis

4

  1. Turn OFF the ignition.
  2. Disconnect a spark plug wire.
  3. Install the J 26792 Spark Tester to the spark plug wire.
  4. Attempt to start the engine.

Does the J 26792 spark?

--

Go to Step 5

Go to Electronic Ignition (EI) System Diagnosis

5

Command the fuel pump ON with a scan tool.

Does the fuel pump turn ON?

--

Go to Step 6

Go to Fuel Pump Electrical Circuit Diagnosis

6

While monitoring the Cylinder 1-6 Injector Circuit Status parameters with a scan tool, crank the engine.

Do all of the Cylinder Injector Circuit Status parameters display OK while cranking the engine?

--

Go to Step 7

Go to Fuel Injector Circuit Diagnosis

7

  1. Turn OFF the ignition.
  2. Install all disconnected components.
  3. Install the J 34730-1A Fuel Pressure Gage. Refer to Fuel System Diagnosis .
  4. Turn ON the ignition, with the engine OFF.
  5. Command the fuel pump ON with a scan tool.

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

358-405 kPa

(52-59 psi)

Go to Step 8

Go to Fuel System Diagnosis

8

Inspect for the following conditions:

    • Collapsed air intake duct
    • Restricted air filter element
        Refer to Air Cleaner Element Replacement .
    • Spark plugs for being gas or coolant fouled
        Refer to Spark Plug Inspection . If the spark plugs are fouled, determine what caused the condition.
    • Engine mechanical condition -- For example, worn timing chain and gears, low compression
        Refer to Symptoms - Engine Mechanical and Engine Compression Test in Engine Mechanical.
    • Restricted exhaust system
        Refer to Restricted Exhaust in Engine Exhaust.
    • The engine coolant temperature (ECT) sensor is NOT close to the actual engine temperature. Refer to DTC P0128 .
    • Compare the manifold absolute pressure/barometric pressure (MAP/BARO) parameters to another vehicle. The parameters should be close in value. Refer to Manifold Absolute Pressure Sensor Diagnosis .
    • Throttle position (TP) sensor for being stuck in range
        Refer to DTC P0121 .

Did you find and correct the condition?

--

Go to Step 9

Go to Diagnostic Aids

9

  1. Clear the DTCs with a scan tool.
  2. Attempt to start the engine.

Does the engine start and continue to operate?

--

Go to Step 10

Go to Step 2

10

  1. Allow the engine to reach operating temperature.
  2. Observe the DTC information with a scan tool.

Are there any DTCs that have not been diagnosed?

--

Go to Diagnostic Trouble Code (DTC) List

System OK