P054A Cold start Exhaust Camshaft position timing Over-Advanced - Bank 1 sensor 2

P054A code - Cam phasing is required on a cold start in order to meet the emissions targets. On cold start, the Powertrain Control Module (PCM) commands the Camshaft to a predetermined target position and monitors the Camshafts to ensure that they are in the desired positions. There are four camshafts and two camshaft position (CMP) sensor. Each CMP sensor will detect the position pf both camshafts on its correlating engine bank.


When monitored, after an engine off time of more than 60 minutes, battery voltage is above 10.7 volts, engine cold start condition, which is determined by the difference between the engine coolant temperature and ambient temperature at engine start up being less that 15°C (59°F), engine start up coolant temperature is above -7°C (19.4°F), engine oil temperature is between -10°C (14°F) and 188°C (370°F), no Cam/Crank misalignment, Camshaft slow response, engine Oil Pressure Sensor or engine oil temperature sensor DTC present, at idle and vehicle speed is below 2 mph (On cold start, when the above enable conditions are met, the PCM will command the Bank 1 Exhaust Cam phaser to a predetermined modeled target position and monitor the actual position of the phaser to see if it is whitin a calibrated threshold of the target, the Cold start monitor diagnostic will stop running if any of the following conditions occur : Accelerator pedal is pressed causing the engine to come off idle, The engine stalls, the engine run time or diagnostic testing time exceeds a calibrated threshold.

Set conditions, the actual Bank 1 Exhaust Cam position is more than 7° advanced (angular variation) from its targeted position for at least 4 seconds.

Possible causes:
  • Engine oil level low
  • Incorrect or contaminated engine oil
  • Insufficient oil pressure to the Exhaust Cam phaser during cold start condition
  •  Camshaft 1/2 oil control valve sticking
  • Camshaft 1/2 Phaser
  • Restricted intake air system
  • Fuel Contamination
  • ETC Motor/Throttle Body
  • Camshaft position sensor wire harness
  • Camshaft position sensor

Diagnostic test P054A code

Step 1. Check DTC
During a cold start, if the engine speed drops below a calibrated minimum idle speed threshold, the base engine control monitor in the PCM will put the Camshaft back to lock pin position.
The Camshaft will stay at lock pin until the speed goes back above a calibrated threshold. During this period the cold start monitor diagnostic sees the Camshaft at lock pin and outside of the calibrated threshold and fail.Therefore, anything that can cause a stumble or drip in idle speed at start up can cause this DTC to set. Another likely cause can be a lack of oil to the camshaft phaser at initial start up due to excessive tarnish or sludge in the oil passages, incorrect viscosity oil or oil filter, a tarnished Cam phaser oil control valve sticking in cold weater, or oil drained back out of the phaser from an period without the engine being started. If this fault is not accompained by any other Crank/Cam Misalignment, Camshaft position performance or Camshaft position actuator circuit faults, it is unlikely that the Camshaft or Cam phasing hardware is at fault. Turn the ignition on, with the scan tool, read DTC.

Are there any Crank/Cam misalignment, Camshaft position performance or Camshaft position actuator circuit DTC present along with this DTC ?

YES, perform the diagnostic procedure for those DTC before continuing.
NO, go to step 2.

Step 2. Check the air filter
Remove and inspect the Air Filter and air intake duct work.

Is the Air Filter dirty or any restrictions found ?

YES, replace the Air Filter or remove the obstruction.
NO, go to step 3.

Step 3. Contaminated Fuel
Inspect the fuel for contamination (Dirty, water, or other foreign material)

Is the fuel contaminated ?

YES, drain the Fuel the tank into an approved gas holding tank and add clean fuel.
NO, go to step 4.

Step 4. Throttle plate inspection
Turn the ignition off, remove the Air Cleaner assembly from the Throttle Body.
Check for any signs of a foreign material (Ice, dirt, or excessive carbon build up) on the Throttle plate or in the bore causing the Throttle plate to stick or restrict airflow.

Were any signs of foreign material or scoring of the throttle plate or bore found ?

YES, remove the debris if possible or replace the Throttle Body Assembly. Disconnected the battery when replacing the Throttle Body Assembly.
After installation is complete, use a scan tool and select the ETC REALERN function.

NO, go to step 5.

Step 5. Camshaft position sensor circuit wiring or connectors
Turn the ignition off, using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Camshaft position sensor and the Powertrain Control Module (PCM).
Look for any chafed, pierched, pinched or partially broken wirs.

Verify that there is good pin to terminal contact in the Camshaft position sensor and the Powertrain Control Module connectors.
Look for broken, bent, pushed out or corroded terminals.
Inspect the Camshaft position sensor for conditions such as loose mounting screws, damage or cracks.

Were any problems found ?

YES, repair as necessary.
NO, check for any mechanical issues that could cause this condition including but not limited to vacuum leaks, low cylinder compression, restriction in airflow in the intake air system, valvetrain issues, etc.

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