P0008

What it means

P0008 means the engine control unit has found that the relationship between the crankshaft and camshaft position signals on Bank 1 is outside the expected range, so the engine position system is not performing correctly. The control unit compares the two signals and sets the code when the correlation is wrong, which usually points to a timing problem, a signal fault or an issue with the variable timing system. The exact cause and the engines affected depend on the model and engine.

Symptoms

• Engine warning light on
• Hard starting or extended cranking
• Rough idle or misfire
• Loss of power and poor acceleration
• Poor fuel economy
• Engine stalling or running in limp mode

Possible causes

• Stretched timing chain, worn tensioner or guides, or timing belt that has jumped a tooth, so the crank and cam timing is outlikely
• Faulty or contaminated crankshaft or camshaft position sensor, or a damaged reluctor or trigger wheellikely
• Damaged wiring, poor connections or corrosion in the crank or cam sensor circuitspossible
• Variable valve timing fault, such as a sticking actuator or solenoid, or low or dirty engine oil affecting its operationpossible
• Timing components fitted incorrectly after previous engine workpossible
• Faulty engine control unit or an outdated calibration where the manufacturer has identified one as a known cause for the enginerare

How to diagnose

1. Read all stored codes and freeze frame data, noting engine speed, temperature and load when the fault set, and look for related cam, crank or misfire codes
2. Check engine oil level and condition, as low or sludgy oil affects timing chains and variable timing systems
3. Inspect the crank and cam sensor wiring and connectors for damage, chafing, oil contamination and corrosion
4. Inspect the sensors and their mounting for damage, debris or looseness, and check the trigger wheels where accessible
5. View live data for cam and crank signals and variable timing angles, comparing actual with commanded values
6. Check the crank and cam signal patterns with an oscilloscope to confirm signal quality and correlation
7. Check the valve timing against the manufacturer's procedure, and measure timing chain stretch where the model allows
8. Check for manufacturer service information on known faults and updates for the specific engine

How to fix

• Replace the timing chain, tensioner and guides, or the timing belt and related parts, and set the timing to specification
• Replace the faulty crank or cam position sensor, or repair a damaged trigger wheel
• Repair or replace damaged wiring and connectors in the sensor circuits
• Replace the faulty variable valve timing actuator or solenoid, and change the oil and filter to the correct grade
• Correct incorrectly fitted timing components and reset the timing to specification
• Update or reprogram the engine control unit only if the manufacturer lists it as a fix for this fault

Can I keep driving?

Nearby codes

• P0007GenericFuel Shutoff Valve A Control Circuit High
• P0009GenericEngine Position System Performance Bank 2