I just bought a 2001 bmw x5 with the 3.0 and had the check engine and i get the P0369 Exhaust Camshaft position Sensor it runs fine but once and a while it will have a rough idle and decrease in power which happens maybe 1-2 times a week.My question is where is this sensor located and is it a do it yourself type thing or is major mechanical work required any help is greatly appreciated