P0008: Engine Position System Performance (Bank 1)
Severity: high
What it means: The engine computer sees the camshaft and crankshaft positions on bank 1 out of their expected relationship. On many engines that points to a stretched timing chain.
Safe to drive? Short trips only, and get it checked soon. A badly stretched chain can jump a tooth or break and damage the engine.
Common symptoms
- Check-engine light
- Rattle at startup
- Rough running or reduced power
- Often set with P0016, P0017 or P0009
Likely causes, ranked
- Stretched timing chainShop
- Low oil level or overdue oil changesDIY
- Worn chain tensioner or guidesShop
- Cam or crank sensor or wiring faultShop
Vehicle-specific notes
- 2010–2011 Buick LaCrosse: 3.6L V6: GM bulletin 12-06-01-009F ties P0008, P0009, P0016, P0017, P0018 and P0019 to timing chain stretch on GM's High Feature V6 and lists timing chain kits for the repair. GM says idler sprockets, cam actuators and guides usually don't need replacing for chain stretch. Read the full answer · Source
What it means: The engine computer sees the camshaft and crankshaft positions on bank 1 out of their expected relationship. On many engines that points to a stretched timing chain.
Severity: High. Safe to drive? Short trips only, and get it checked soon. A badly stretched chain can jump a tooth or break and damage the engine.
DIY or shop?
Check the oil level first. Confirming and repairing chain stretch is a shop job.
Before you replace parts
- Read all stored codes and freeze-frame data. Fix misfire, fuel or sensor codes before chasing emissions codes.
- Check the simple things first: connectors, vacuum hoses, fluid levels and the gas cap.
- Clear the code only after a repair, then confirm it stays off after a few drives.
- Check your VIN for recalls and service bulletins.
Safety / mechanic note
Verify with a mechanic if you notice drivability changes, warning lights or overheating. A code points to a circuit or system, not always a specific part.