New Si owner - rough idle after going through downpour
Just on my second week of si ownership, excellent car by the way.
GWLS has given me the link to the forum as we converse on another club site and after having problems with rough idle after starting the si yesterday morning hey presto there is a running link on the subject.
Does this sound familiar-
Monday was driving through big downpours car was fine, yesterday started the si and had really rough idle sounded like 3 pots firing and revs seem to go up to compensate. Driving the car there was no loss of performance but changing gears and the revs dropping towards idle gave uneven running. Left the car parked for a couple of hours thinking the engine bay heat might dry up moisture on whatever was causing problem.
No luck so called into BMW Sycamores in Peterborough (really good response even though I hadn't bought the car from them) half an hour later the Tech. explained that something had caused the idle map in the computer to drop out and go into emergency run mode this hadn't affected the the main engine map he had reprogrammed the computer and it was back to normal (I subsequently did about 15 start stops during the afternoon all ok) the tech further explained that the early E90 had an engine management loom issue causing similar problems that required them to be replaced. 06 cars shouldn't have the problem but if I had the problem again he would look at changing the loom and meanwhile would report the problem to the BMW Techs problem centre. A short break while I just start the car as we had storms again last night... Si starts fine also cild start came in which didn't happen when the rough idle manifested itself.
Hope this helps as we do seem to have a similar problem.
Carbon Black/blue 320 Si