Circuit/System Verification
WARNING: This page is about a different car, the 2022 Cadillac CT5. 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 DTC P0117, P0118, P0122, P0123, P0201 - P0208, P0222, P0223, P0300 - P0308, P0335, P0336, P0351 - P0358, P0562, P0563, P0601 - P0604, P0606, P0607, P062F, P0633, P0685, P0690, P1631, P1682, or P2610 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 indicator stays illuminated or is flashing
Refer to Diagnostic Trouble Code (DTC) List - Vehicle .
- Go to next step: If the indicator does not stay illuminated and is not flashing
- If the indicator stays illuminated or is flashing
- Verify the scan tool Engine Speed parameter is greater than 0 RPM while cranking the engine.
- If 0 RPM
Refer to DTC P0335 or P0336 for further diagnosis.
- Go to next step: If greater than 0 RPM
- If 0 RPM
- Connect the EL 26792 HEI Spark Tester between the boot of a spark plug wire and ground.
- Perform the spark test on at least one cylinder for each cylinder 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
- Ignition ON.
- If the engine is too hot, high fuel pressure readings may result due to hot soak fuel boiling. Allow the engine coolant temperature to cool down to below 60° C (150°F) before attempting to verify fuel pressure.
- The scan tool Fuel Pump Enable may need to be commanded On a few times in order to obtain the highest possible fuel pressure.
- Command the Fuel Pump Enable On several times with a scan tool.
- Verify the scan tool Fuel Pressure Sensor parameter is between 320 - 608 kPa (46 - 88 psi) with the fuel pump running.
- If not within the specified range
Refer to Fuel System Diagnosis .
- Go to next step: If within the specified range
- If not within the specified range
- Verify the fuel pressure, after the fuel pump has turned OFF, decreases to 468 - 544 kPa (68 - 79 psi) and does not decrease greater than 34 kPa (5 psi) in 1 minute.
- If not within the specified range
Refer to Fuel System Diagnosis .
- Go to next step: If within the specified range
- If not within the specified range
- Verify the conditions listed below do not exist:
- A stuck camshaft position actuator solenoid valve. It may be necessary to perform a dynamic test on the valve to verify correct operation. Refer to DTC P0010, P0011, P2088, or P2089 for instructions.
- Collapsed air intake duct to the throttle body
- Restricted air filter element
- Spark plugs for being fouled
- A skewed manifold absolute pressure (MAP) sensor - Refer to DTC P0107 or P0108 .
- A skewed engine coolant temperature (ECT) sensor - Refer to DTC P0117, P0118, or P0119 .
- Exhaust system restricted - Refer to Restricted Exhaust .
- Fuel contamination - Refer to Alcohol/Contaminants-in-Fuel Diagnosis .
- Engine mechanical condition, such as worn timing chain and gears or low compression - Refer to Symptoms - Engine Mechanical , or Engine Compression Test .
- If a condition exists
Repair as necessary.
- Go to next step: If no conditions exist
- All OK.
NOTE:
NOTE:
NOTE:
The fuel pressure may vary slightly when the fuel pump stops running. After the fuel pump stops running, the fuel pressure should stabilize and remain constant.