GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Isuzu 🢒 2006 🢒 Ascender - 2WD 🢒 Engine 🢒 Engine Controls - 6.0L 🢒 Engine Cranks But Does Not Run

Description

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

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

Step

Action

Values

Yes

No

Schematic Reference: Engine Controls Schematics

Connector End View Reference: Engine Control Module Connector End Views or Engine Controls Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

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Go to Step 2

Go to Diagnostic System Check - Vehicle

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

Does the scan tool display DTCs P0101, P0108, P0230, P0335, P0336, P0601, P0602, P0604, P0606, P0607, P0641, P0651, P0685, P0689, P0690, P1621, P1630, P1631, P1682, or P2610?

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Go to Diagnostic Trouble Code (DTC) List - Vehicle

Go to Step 3

3

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

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Go to Diagnostic Trouble Code (DTC) List - Vehicle

Go to Step 4

4
  1. Turn ON the ignition, with the engine OFF.
  2. Probe both sides of the fuses located in the underhood electrical center listed below using a test lamp connected to ground.
    3. • ENG 1 fuse
    • O2A fuse
    • O2B fuse
    • TAC fuse
    •  INJ A
    •  INJ B

Does the test lamp illuminate on at least one side of each fuse?

--

Go to Step 5

Go to Powertrain Relay Diagnosis

5

Command the fuel pump ON with a scan tool.

Does the fuel pump operate?

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Go to Step 6

Go to Fuel Pump Electrical Circuit Diagnosis

6

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

Does the spark tester spark?

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Go to Step 7

Go to Electronic Ignition (EI) System Diagnosis

7
  1. Turn OFF the ignition.
  2. Install a fuel pressure gage. Refer to Fuel Pressure Gage Installation and Removal .

    3. Important: You may need to command the fuel pump ON a few times to obtain the highest possible fuel pressure.

  3. Turn ON the ignition, with the engine OFF.
  4. Command the fuel pump ON with a scan tool.
  5. Observe the fuel pressure while the fuel pump is operating.

Is the fuel pressure within the specified range?

379-427 kPa

(55-62 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 fouled--Refer to Spark Plug Inspection . If the spark plugs are fouled, determine what caused the condition.
    • Engine mechanical condition, for example, broken timing chain, low compression--Refer to Engine Compression Test .
    • 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 .
    • Compare the MAP parameter to another vehicle. The parameters should be close in value. Refer to DTC P0106 .

Did you complete the action?

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Go to Step 9

Go to Symptoms - Engine Controls

9
  1. Clear the DTCs with a scan tool.
  2. Attempt to start the engine.

Does the engine start and continue to operate?

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Go to Step 10

Go to Step 2

10
  1. Idle the engine.
  2. Allow the engine to reach operating temperature.
  3. Observe the DTC information with a scan tool.

Are any DTCs displayed?

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Go to Diagnostic Trouble Code (DTC) List - Vehicle

System OK