Circuit/System Verification
WARNING: This page is about a different car, the 2019 GMC Savana 3500, 2019 GMC Savana 2500, 2019 Chevrolet Express 3500, and 2019 Chevrolet Express 2500. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
This diagnostic assumes the following:
- The battery is completely charged.
- The engine cranking speed is acceptable.
- There is adequate fuel in the fuel tank.
- Crank the engine for up to 15 seconds.
- Verify that DTC P0117, P0118, P0122, P0123, P0201 - P0208, P0222, P0223, P0230, P0300 - P0308, P0335, P0336, P0351 - P0358, P0562, P0563, P0601 - P0604, P0606, P0607, P060D, P062F, P0633, P0685, P0690, P1631, P1682, P2610, or P264F is not set.
- If any of the DTCs are set
Refer to Diagnostic Trouble Code (DTC) List - Vehicle .
- Go to next step: If none of the DTCs are set
- If any of the DTCs are set
- Ignition ON
- Verify the security indicator on the instrument cluster illuminates momentarily.
- If the security indicator stays ON or is flashing
Review the Diagnostic Trouble Code (DTC) List - Vehicle , for Immobilizer system DTCs. For additional information, refer to Immobilizer Description and Operation .
- Go to next step: If the security indicator does not stay ON and is not flashing
- If the security indicator stays ON or is flashing
- Verify the scan tool Engine Speed parameter displays greater than 0 RPM while cranking the engine.
- If 0 RPM
Refer to DTC P0335 or P0336 .
- Go to next step: If greater than 0 RPM
- If 0 RPM
- Ignition OFF, disconnect a spark plug wire from one of the spark plugs.
- Connect a EL 26792 HEI Spark Tester between the boot of the spark plug wire and ground.
- Perform the spark test on at least one cylinder of each engine bank.
- An erratic or weak spark is considered a no spark condition.
- Verify the spark tester sparks while cranking the engine.
- If the spark tester does not spark
Refer to Electronic Ignition System Diagnosis .
- Go to next step: If the spark tester sparks
- If the spark tester does not spark
- Verify the LPG fuel system operates correctly. Perform the Fuel System Diagnosis (Without FPCM) , or Fuel System Diagnosis (FPCM) .
- If the LPG fuel system does not operate correctly
Repair as necessary.
- Go to next step: If the LPG fuel system operates correctly
- If the LPG fuel system does not operate correctly
- Verify the conditions listed below do not exist:
- Collapsed air intake duct to the throttle body
- Restricted air filter element
- Gas or oil fouled spark plugs - Refer to Spark Plug Inspection
- A skewed manifold absolute pressure (MAP) sensor - Refer to DTC P0106 .
- A skewed engine coolant temperature (ECT) sensor - Refer to DTC P0116-P0119 .
- Restricted exhaust system - Refer to Restricted Exhaust .
- An engine mechanical condition, for example, worn timing chain and gears or low compression - Refer to Symptoms - Engine Mechanical , and Camshaft Timing Chain and Sprocket Cleaning and Inspection .
- If a condition exists
Repair as necessary.
- Go to next step: If no condition exists
- All OK.
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