Crank Hub Slip / Timing Risk
SeriousEngineHighly publicised on tuned S55 cars, crank-hub slip can throw engine timing out and destroy the valvetrain. Stock cars are less vulnerable, but mapped examples deserve extra caution.
Most affected: F80 M3
Typical symptoms
- •Sudden misfire after a hard pull
- •Engine light and loss of power after overrun or kickdown
What to inspect before you buy
- ✓Ask whether the car is mapped or has a pinned crank-hub fix
- ✓Be wary of drag-race or repeated-launch use