After dealing with the stealers for couple of days I decided that forums know better anyway ! Couple of weeks ago I bought an '04 545i 40000 mls, and hence the title it has an idle problem, not just when its cold, always! As the car is parked or at the light the rpm's slightly go up and down continuously, and sometimes a little more, even that you can feel a slight shiver...
Dealer reprogrammed the car and "re-learned" its valvetronics(I believe) WHY? and charged me since CPO does not cover this??!! However it didn't do anything ! Now they want to clean its injectors etc. and told me that that also isn't covered by the warranty and it is regular maintenance!!

At this point I just did not want to deal with them anymore and their speculations so I took my car! What do you guys think I should do, and what is the problem? SHould I clean injectors or the top end as they called it?? How can I do it myself? What else could be the problem? Thanks!

 

im having the same problem, no pattern to the vibration, just a hum or shiver when the rpms go to about 500 right? i cleaned injectors with some gas additive from bmw, no help. i brought the car in a week ago they changed the cam sensors, no help. i have a diagnostic tool that told me it was an idle motor so when i go back to the stealer im suggest checking the idle. no performace issue and it goes away once i tap the pedal but it annoying at red lights and when the car is in park. ill let you know how it goes

 

Yep, sounds about right! What additive did you use(I want to try it anyway)...? So far from my research I think it could be dirty intake valves, or more likely a faulty ignition coil... Let me know!!! Thanks....

 

Have you cleaned the MAF yet? Start with the easy stuff

 

I was going to, but what tool do I need to take it off?? On my e46 M3 it was a 6 star torx on this one its five... Where can I buy that??

 

If it was any other older beema I would say idle control valve, did one on my old E34 525i sport...........

 

I'm no mechanic, but the problem maybe simply be fixed just by replacing the spark plugs. I've had that problem with a 325is once. It only had 20000 mls. Where did you buy the car from? What's the history? DIY the plugs. You might get lucky like I did and avoid costly/unneccessary repairs by the dealer. STEVE

 

I just used a standard "torx" bit, don't remember the size....but there are 2 of them holding the maf to the housing. Unscrew these, remove the plug connector and the maf will slide right out

 

its most likely carbon build up in the throttle body and intake. they sell those cleaners @ auto parts store.

 

Agree with the spark plugs - how many miles do you have on your car??? I had this exact same problem - changing the sparks out [not covered by CPO] completely solved the problem! Good luck to you...there was never a diagnostic test at BMW that confirmed this so it's a bit of a crapshoot BUT...this would be a good place to start if your nearing or over 50K miles in any case...