Unofficialbmw.com

[hawaiiangordy]

Just FYI: My m50 engine has for the past 3 or 4 months suffered from a "knock-like" noise which developed after the engine warmed up. I had been concerned that it was the vanos or that the timing chain tensioner needed replacing.

I took the car in to Knightwerks in Honolulu, Hawaii to check out and he id'ed the problem immediately. According to Tim at Knightwerks, the 3 series has a tendency for the spark plugs to become loose and thence develop a compression leak (hence the "knock-like" sound at warm-up) This was especially true, as BMW has a tendency to NOT torque down the spark plugs from the factory floor. Take a $230 lesson from me and take some time out over the weekend to service those spark plugs. You will be able to enjoy those dollars entertaining at the local watering hole, instead of dishing it out like I did.

See you on the road!