P052C

What it means

P052C is the generic code for the bank 2 'A' camshaft (normally the intake) being over-advanced during a cold start. The engine control unit compares the commanded cam timing with the actual position from the camshaft and crankshaft sensors. If the cam sits further advanced than commanded, beyond a set tolerance, while the engine is cold, it logs this fault.

Symptoms

• Check engine light on
• Rough or unstable idle on a cold start
• Hard starting or extended cranking when cold
• Hesitation or reduced power until the engine warms up
• Rattle or ticking from the timing drive area on start-up
• Poor fuel economy

Possible causes

• Faulty cam phaser (variable valve timing actuator) on bank 2, sticking or wornlikely
• Faulty, sticking or blocked oil control solenoid on bank 2likely
• Low, dirty, degraded or wrong-grade engine oil, or blocked oil passages or screens feeding the phaserlikely
• Stretched or jumped timing chain or belt, or a worn tensioner or guides, giving incorrect cam timingpossible
• Wiring or connector fault in the solenoid circuit or cam and crank position sensor circuitspossible
• Faulty camshaft or crankshaft position sensor, or a damaged reluctor wheel, giving false position readingspossible
• Engine control unit software fault where the manufacturer has issued an updated calibrationrare

How to diagnose

1. Read all stored and pending codes and the freeze frame data, noting engine temperature, oil temperature and rpm when the fault set
2. Check the engine oil level, condition and grade against the manufacturer's specification, and check the service history
3. Inspect the wiring and connectors to the bank 2 oil control solenoid and the cam and crank sensors for damage, corrosion, oil contamination or chafing
4. Use live data to compare commanded and actual cam angle on bank 2 from a cold start, and compare with bank 1 where fitted
5. Test the oil control solenoid's resistance and operation against the manufacturer's data, and inspect its screen for debris
6. Check the cam and crank sensor signals and the reluctor wheels for correct pattern and condition
7. Check the mechanical timing for chain stretch or incorrect alignment, using the manufacturer's procedure for the engine
8. Check for applicable technical bulletins or software updates for the specific model and engine

How to fix

• Change the engine oil and filter to the correct grade and specification, and correct the oil level
• Replace the faulty oil control solenoid and clean or replace its filter screen
• Replace the cam phaser if it is worn, sticking or failing its operation test
• Repair damaged wiring or connectors, or replace a faulty cam or crank sensor
• Replace the timing chain, tensioner and guides if the timing is out of specification
• Apply an updated engine control unit calibration only if the manufacturer lists it as a fix for this fault

Can I keep driving?

Nearby codes

• P052BGenericCold Start A Camshaft Position Timing Over-Retarded Bank 1
• P052DGenericCold Start A Camshaft Position Timing Over-Retarded Bank 2