P0024

What it means

P0024 means the engine control unit has found that the bank 2 'B' camshaft (usually the exhaust camshaft, though this depends on the engine) is further advanced than commanded, or that the variable valve timing system is not performing as expected. The ECU compares the camshaft position sensor signal with the crankshaft position signal and sees a timing error beyond its limit.

Symptoms

• Engine warning light on
• Rough or unstable idle
• Hesitation or reduced power under acceleration
• Poor fuel economy
• Occasional stalling or hard starting
• Rattling or ticking noise from the timing area on some engines

Possible causes

• Low, dirty or degraded engine oil, or the wrong oil grade, affecting the variable timing actuatorlikely
• Faulty or sticking camshaft phaser control solenoid (oil control valve) on bank 2likely
• Blocked oil passages or a clogged solenoid screen restricting oil flow to the phaserpossible
• Wiring or connector fault in the solenoid or camshaft sensor circuit (chafing, corrosion, poor pin tension)possible
• Stretched timing chain or belt, worn tensioner or guides, or timing set out of alignmentpossible
• Faulty camshaft or crankshaft position sensor, or damaged reluctor wheelrare
• Worn or failed camshaft phaser/actuator, or an outdated ECU calibration where the manufacturer has issued an update for this faultrare

How to diagnose

1. Read all stored and pending codes and the freeze frame data; note engine temperature, load and speed when the fault set, and check for related cam or crank sensor codes
2. Check the engine oil level, condition and specification against the manufacturer's requirement, and note the service history
3. Visually inspect the bank 2 phaser solenoid and camshaft sensor wiring and connectors for damage, oil contamination, corrosion or loose pins
4. Using a scan tool with live data, compare commanded and actual camshaft position on bank 2 at idle and under load
5. Test the solenoid's resistance and supply, ground and control signals against the manufacturer's specification, and check that it operates when commanded
6. Remove the solenoid and inspect it and its filter screen for debris, sludge or sticking; check the oil feed passages if the engine design allows
7. Check the camshaft and crankshaft sensor signals, and inspect timing chain or belt condition and correlation if timing stretch is suspected
8. Check for applicable technical service bulletins or calibration updates for the specific model and engine

How to fix

• Change the oil and filter to the correct grade and specification, and correct the oil level
• Replace the faulty bank 2 camshaft phaser solenoid and clean or replace its filter screen
• Repair or replace damaged wiring and connectors in the solenoid or sensor circuit
• Replace a faulty camshaft or crankshaft position sensor
• Replace the timing chain or belt, tensioner and guides, and reset the timing correctly, or replace a worn phaser
• Apply a manufacturer-issued ECU calibration update only where the fault is a known software issue for that engine

Can I keep driving?

Nearby codes

• P0023GenericB Camshaft Position Actuator A Control Circuit/Open Bank 2
• P0025GenericB Camshaft Position - Timing Over-Retarded Bank 2