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
    • There is adequate fuel in the fuel tank

Step

Action

Value(s)

Yes

No

1

Did you perform the Diagnostic System Check-Engine Controls?

--

Go to Step 2

Go to Diagnostic System Check - Engine Controls

2

Does the scan tool display any U type DTCs ?

 

Go To Diagnostic Trouble Code (DTC) List In Data Link Communications

Go to Step 3

3

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

Does the scan tool display DTCs P0102, P0108, P0201-P0206, P0230, P0231, P0232, P0341, P0342, P0343, P0335, P0338, P0601, P0602, P0603, P0604, P0606, P0610, P0627, P0628, P0629, P1629, P1630, P1631, P1682?

--

Go to Diagnostic Trouble Code (DTC) List

Go to Step 4

4

Does the scan tool display any body control module (BCM) vehicle theft deterrent (VTD) DTCs?

--

Go to Diagnostic Trouble Code (DTC) List in Theft Deterrent

Go to Step 5

5

Command the fuel pump ON with a scan tool.

Does the fuel pump operate?

--

Go to Step 6

Go to Fuel Pump Electrical Circuit Diagnosis

6

  1. Disconnect the harness connector of both ignition module assemblies.
  2. Important: The fuel injector test lamp will be dim, which is normal. If using a different fuel injector test lamp, the bulb resistance must be 4 ohms or less.

  3. Using jumper wires, connect the fuel injector test lamp J 34730-405 Injector Test Lamp (Noid Light) between the ignition voltage circuit and the ignition control (IC) 1 circuit of the ignition module harness connector.
  4. Command the ignition coil cyl. 1 ON with a scan tool.
  5. Repeat steps 3 and 4 for the remaining IC circuits.

Does the fuel injector test lamp flash for all IC circuits?

--

Go to Step 7

Go to Electronic Ignition (EI) System Diagnosis

7

  1. Turn OFF the ignition.
  2. Install a Gage Bar Set (SA9127E). Refer to Fuel Pressure Gage Installation and Removal .
  3. Turn ON the ignition, with the engine OFF.
  4. Command the fuel pump ON with a scan tool.

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

345- 413 kPa (50-60 psi)

Go to Step 8

Go to Fuel System Diagnosis

8

Inspect for the following conditions:

    • A collapsed air intake duct
    • A restricted air filter element--Refer to Air Cleaner Element Replacement .
    • The spark plugs for being gas or coolant fouled--Refer to Spark Plug Inspection and Spark Plug Replacement . If the spark plugs are fouled, determine what caused the condition.
    • Any engine mechanical conditions, worn timing chain and gears, or low compression--Refer to Engine Compression Test in Engine Mechanical.
    • A restricted exhaust system--Refer to Restricted Exhaust in Engine Exhaust.
    • An engine coolant temperature (ECT) sensor that has shifted in value--Refer to Temperature Versus Resistance .
    • Contaminated fuel--Refer to Alcohol/Contaminants-in-Fuel Diagnosis .

Did you complete the action?

--

Go to Step 9

--

9

  1. Clear the DTCs with a scan tool.
  2. Turn OFF the ignition for 30 seconds.
  3. Attempt to start the engine.

Does the engine start, then continue to run?

--

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