Hi, have a a6 2000 year 1.8 petrol. Car drives and starts perfect, at least for a while, then simply cuts out and refuse to start for up to 10 minutes, start again and then runtime reduced before next cutout. Had a waterleak before and that was just fixed. Plastic hose fitting connection on back of engine o-ring leaked. The oil sensor warning light has just came back on. Still orange. Worth mentioning that when the car warning displayed oil sensor whilst driving, the display changed very briefly to a red oil light upon cutting off engine. This sign disappeared and went back to amber oil sensor light when restarted car after waiting period.