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Engine Cranks but Does Not Run: Description

WARNING: This page is about a different car, the 2004 GMC Sierra and 2004 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.

The Engine Cranks but Does Not Run diagnostic table is an organized approach to identifying a condition that prevents an engine from starting. 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:

Engine Cranks but Does Not Run

Step Action Value(s) Yes No
Schematic Reference:  Engine Controls Schematics 
Connector End View Reference:  Engine Controls Connector End Views  or  Powertrain Control Module (PCM) Connector End Views 
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 P0230, P0335, P0336, P0601, P0602, P0604, P1626, P1631, or P1683?		 - Go to Diagnostic Trouble Code (DTC) List Go to Step 3 
3 Does the scan tool display any body control module (BCM) vehicle theft deterrent (VTD) DTCs? - Go to Diagnostic System Check - Theft Deterrent in Theft Deterrent Go to Step 4 
4 Probe both sides of the following fuses with a test lamp that is connected to a good ground:
  • ECM 1
  • INJ A
  • INJ B

Does the test lamp illuminate on at least one side of all of the fuses?		 - Go to Step 5  Go to Ignition Relay Diagnosis 
5
  1. Attempt to start the engine.
  2. Observe the Engine Speed parameter with a scan tool, while the engine is cranking.
Does the engine speed increment?		 - Go to Step 6  Go to Distributor Ignition (DI) System Diagnosis 
6 Monitor the Ignition 1 Signal Voltage parameter with a scan tool.
Is the Ignition 1 Signal Voltage parameter at the specified value?		 B+ Go to Step 7  Go to Step 11 
7 Command the fuel pump ON with a scan tool.
Does the fuel pump turn ON?		 - Go to Step 8  Go to Fuel Pump Electrical Circuit Diagnosis 
8
  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 spark tester spark?		 - Go to Step 9  Go to Distributor Ignition (DI) System Diagnosis 
9
  1. Turn OFF the ignition.
  2. Install the J 34730-1A  fuel pressure gage. Refer to Fuel System Diagnosis  .
  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?		 379-427 kPa
(55-62 psi)		 Go to Step 10  Go to Fuel System Diagnosis 
10 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 . If the spark plugs are fouled, determine what caused the condition.
  • Any engine mechanical condition, such as a worn timing chain, gears and low compression-Refer to Symptoms - Engine Mechanical in Engine Mechanical 4.3L.
  • A 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 P0125 .
  • Compare manifold absolute pressure/barometric pressure (MAP/BARO) parameters to another vehicle. The parameters should be close in value. Refer to DTC P0106 .
  • The throttle position (TP) sensor for being stuck in range-Refer to DTC P0121 .

Did you find complete the action?		 - Go to Step 14  -
11
  1. Test the ignition 1 signal voltage circuit for an open or for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
  2. Replace the fuse if necessary.
Did you find and correct the condition?		 - Go to Step 14  Go to Step 12 
12 Inspect for poor connections at the harness connector of the PCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 14  Go to Step 13 
13 Replace the PCM. Refer to Powertrain Control Module (PCM) Replacement .
Did you complete the replacement?		 - Go to Step 14  -
14
  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 15  Go to Step 2 
15
  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?		 - Go to Diagnostic Trouble Code (DTC) List System OK
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