Idle probs, yeah I've used the seach

[Cyruz]

My 325i has developed an unhealthy idle. The car was fully serviced 500 miles ago with new belts, water pump, blue sensor, oil+filter, coolant, dist+rotor, air filter and spark plugs.

I've been checking all the old threads and compiled the a list of possible things. Perhaps an air leak meaning the engine is running rich/poor does smell v.rich when starting from cold. Does the standard air box make a hissing sound or is this leak .

Gas mileage is particually bad when cold doing about 15-10mpg at 30mph in 3rd under only slight load. The car also smoke loads when cold (I checked for white crap on dipstick and oil cap) but has a hole in the exhaust, so could be condensation, but it was really heavily pooring out last night to the point where it was blocking rear view mirror at idle.

Thanks in advance...

[peterjk]

Check the idle control valve first. If it's surging up and down then it may need cleaning out or if that's no good replace it.

Peter