BMW Repair: Slow M3 e46, volvo s40 t4, bmw technician

Question
Hello Evan,

I just bought an e46 m3 2001 and i live in Mexico City. the car feels fine but i does not appears to be as fast as i thought. I used to have a Volvo S40 T4 MT and it was a lot faster, i know it sounds BS but trust me it was. there are no indicators of something wrong in the car but i took it to a friend of mine repair shop and it showed 2 problems on the camshaft sensors, i do not remember the codes but my friend got advise from a local BMW technician and he said the sensors are practically bullet proof and the real problem might be in the head that was poorly armed. but i know the previous owner and he told me he never change or repair anything involving the head or any engine parts what so ever.
Is there a chance the sensors are bad as the OTC reading shows, and if so, could this be a problem to the car being so slow? any advice is deeply appreciated.

Thanks

Juan

Answer
Juan, that S54 motor inparticular doesn't have a history of having faulty camshaft sensors as do the other six cylinders, but if you have a check engine light on and have fault codes stored then I would replace both intake and exhaust camshaft sensors and o-rings. I believe those sensors are on the backside of the cylinder head. Clear the faults when finished.
-Evan