P0811
Excessive Clutch Slippage
- Severity
- High
- Driving
- Drive only to a garage
The module has measured the clutch slipping more than it should. Engine speed and transmission input speed do not match while the clutch is supposed to be fully engaged, which means the clutch is not holding. On a high-mileage vehicle this usually means the clutch is worn out.
Possible causes
- CommonWorn clutch friction plate
- CommonClutch contaminated with oil from a leaking crankshaft or gearbox seal
- CommonClutch actuator not applying full clamping force
- PossibleCalibration lost, so the module is not clamping fully
- PossibleWarped or glazed pressure plate or flywheel
- PossibleFaulty speed sensor making a healthy clutch look like it is slipping
What you might notice
- Engine speed rises without the car accelerating to match
- Burning smell, especially after a hill or heavy traffic
- Judder when moving off
- Loss of power under acceleration
- Transmission warning message
What to check, in order
- Confirm the slip by driving: in a high gear at low speed, apply throttle and watch whether engine speed climbs faster than road speed. If it does, the clutch really is slipping.
- Run the clutch adaptation procedure and see whether it improves. If it does not, plan for a clutch replacement.
- Look for oil contamination. A leaking crankshaft rear seal or gearbox input seal soaks the clutch and makes it slip, and replacing the clutch without fixing the leak repeats the failure.
- Check the clutch hydraulic circuit for leaks and correct fluid level.
- Stop driving it hard. A slipping clutch overheats fast, and the heat can damage the flywheel - which turns a clutch job into a much more expensive one.
Read this code from your own car
Plug an ELM327 adapter into the OBD-II port under the dashboard. Pin16 reads every stored, pending and permanent code, explains each one like this page does — offline, with no account — and shows what the car recorded when the fault was set.
Where this code sits
P00xxP01xxP02xxP03xxP04xxP05xxP06xxP07xxP08xxP09xxP0AxxP0BxxP0CxxP0DxxP0ExxP0FxxP10xxP11xxP12xxP13xxP14xxP15xxP16xxP17xxP18xxP19xxP1AxxP1BxxP1CxxP1DxxP1ExxP1FxxP20xxP21xxP22xxP23xxP24xxP25xxP26xxP27xxP28xxP29xxP2AxxP2BxxP2CxxP2DxxP2ExxP2FxxP30xxP31xxP32xxP33xxP34xxP35xxP36xxP37xxP38xxP39xxP3AxxP3BxxP3CxxP3DxxP3ExxP3Fxx
Transmission
P0800P0801P0802P0803P0804P0805P0806P0807P0808P0809P0810P0811P0812P0813P0814P0815P0816P0817P0818P0819P0820P0821P0822P0823P0824P0825P0826P0827P0828P0829P0830P0831P0832P0833P0834P0835P0836P0837P0838P0839P0840P0841P0842P0843P0844P0845P0846P0847P0848P0849P0850P0851P0852P0853P0854P0855P0856P0857P0858P0859P0860P0861P0862P0863P0864P0865P0866P0867P0868P0869P0870P0871P0872P0873P0874P0875P0876P0877P0878P0879P0880P0881P0882P0883P0884P0885P0886P0887P0888P0889P0890P0891P0892P0893P0894P0895P0896P0897P0898P0899