For a long time I have been experiencing a roughness for the first quarter of a mile after starting my '03 -530I in the morning. I drive for a long block and when I stop at a stop sign the engine is a bit rough. Once the engine warms up (a few blocks later)there is no reoccurance. Any ideas?
Does your idle fluctuate up and down, to the point where the car feels like it's going to stall and you have to pump the gas pedal to keep it running? Had that problem in my E39 and replaced the idle sensor.
Mike Miller (Tech Talk) said you can try to clean them with some carb/choke cleaner but results can be spotty and that may or not work. Best I can remember it seemed to be, in technical terms, a real bitch to get to. I'm guessing just replace it is the best option.
this can also be your vent tube. About a $120.00 job at an BMW indy.The tube just cracks because its plastic and that it was after 8-years since you have had your car. Mostly this will happen when the weather is cold. Wont happen much in summer. You may even get a check engine light.
Simplest first... Try cleaning your ICV and MAF but if it continues after that, you may have the dreaded VANOS issue... The failing o-rings cause a pressure leak, which translates into a rough cold idle and other fun problems. Hopefully it's just your gummed up ICV or a dirty MAF...many have had great success with the clean up method for both. Check out the links in my helpful sticky at the top of this forum...