I would just add the cautionary advice that when it comes to replacing sensors always use oem branded parts such as Bosch or Seimens do not buy cheap pattern parts from ebay, they seldom work or last long this is particulaly true for Maf sensors if you need to replace that. I have used Hass branded camshaft sensors and found that they do work and last, good enough for a F1 team so good enough for a BMW.