Hi can anyone please offer some advice, I drive a 1999 2.0 z3 auto. While driving along occasionally the EML light will come on the Rev counter needle drops to zero and the water temp gauge goes right over to the red after a few seconds the light goes out and the Rev counter and temp gauge return to normal. I have recently replaced had the o2 sensor after the cat on bank1 replaced and the car serviced. I also replaced the air intake pipe as that had split. I have reset the error codes and this keeps happening. When the EML light comes on if the car is pulling off it appears low on power but otherwise has no effect on the driving of the car if it is moving when it comes on. The error keeps referring to the o2 sensor after the car on bank 1. Am not sure if it is using excessive fuel seem to get approx 30mpg