P0009

What does P0009 mean?

P0009 is a Powertrain (engine, transmission, fuel system) fault code. It indicates: Engine Position System Performance Bank 2.

This is a standardised OBD-II code. The technical definition is the same regardless of the make or model of vehicle, although specific causes and symptoms can vary between vehicles.

Symptoms commonly associated with this code

Symptoms that drivers often report alongside this code. Not all may apply to every case:

• • Engine warning light on, sometimes with a rattle from the front of the engine on cold start
• • Rough, lumpy idle that doesn't smooth out
• • Hesitation or a flat spot when you put your foot down
• • Hard starting, sometimes needing a few extra cranks before it catches
• • The odd misfire or stumble under load
• • Worse fuel economy than you're used to
• • On a badly stretched chain it can drop into limp mode or stall at low revs

Possible causes

Causes commonly associated with P0009, listed in approximate order of typical investigation. The actual cause on a specific vehicle can only be confirmed by professional diagnosis.

1. 1. Stretched timing chain, far and away the usual culprit on higher-mileage engines. The chain wears, the cam timing slips, and the ECU sees bank 2 out of sync. The GM 3.6L V6 (found in Vauxhall Insignia, Antara and some Saab models) is a known offender for this
2. 2. Worn chain tensioners or guides letting the chain slap and lose tension, which produces the same timing error
3. 3. Faulty bank 2 camshaft position sensor reporting a false cam position
4. 4. Low or degraded engine oil, which starves the variable valve timing phaser of oil pressure and stops it holding position. Cheap and worth ruling out first
5. 5. Faulty crankshaft position sensor giving the ECU a bad reference signal
6. 6. Wiring or connector faults on the cam or crank sensor circuits, often corrosion in a connector after years of road salt
7. 7. Damaged or contaminated reluctor ring on the cam or crank that the sensor reads

How mechanics typically diagnose

A typical diagnostic sequence used by mechanics, provided here for educational reference only. Diagnostic work should be performed by a qualified mechanic with the appropriate tools and training.

1. 1. Check the engine oil level and condition before anything else. Low or sludgy oil chokes the VVT phasers and can throw this code on its own, and it's a five minute check that saves you tearing the engine apart for nothing
2. 2. Pull the freeze frame data and note engine speed, load and the sensor readings at the moment it logged. A code that only sets on cold start points more towards a chain or tensioner than a sensor
3. 3. Scan for friends. P0008, P0016 through P0019 and crank/cam correlation codes alongside P0009 strongly suggest the timing itself has slipped rather than a duff sensor
4. 4. Inspect the bank 2 cam sensor and crank sensor wiring and connectors for corrosion, chafing or a loose pin
5. 5. Scope the cam and crank sensor signals together and check the timing relationship between them. A clean signal that's simply out of phase tells you the mechanical timing has moved
6. 6. If the sensors and signals look right, pull the cam cover or upper timing cover and check the timing marks at TDC. A chain that's jumped a tooth or has measurable slack is your answer

Common questions about P0009