Idle problem? - The Unofficial BMW M5 Messageboard (m5board.com)

WGM5 · 26th May 2006, 05:51

I've had my M5 for about 3 months. I still pinch myself to make sure I'm awake. I can't believe I own one.
Recently the car has developed a pronounced pulse at idle when it's cold. Doesn't happen when it's warm. Is this something I should be concerned about? I did a search and didn't come up with anything useful?
The car has 50,000 miles on it. Would replacing the MAFs correct this?
Thanks,
Will

robord535 · 26th May 2006, 11:55

My car use to do it occasionally in the cold - replaced MAFs due to other symptoms (Limp Mode and poor Fuel flow readings) - Never does it now - nothing else revevant changed.

WGM5 · 26th May 2006, 12:45

Thanks,
After reading the thread about the Mafs, seems like it might be the source.
Will
Did you replace them with the VW mafs?

robord535 · 26th May 2006, 14:19

My car has a BMW warranty/service plan and so although my MAFs passed the BMW computer tests, with evidence I showed the dealer from this forum and DavidS's voltage tests, I convinced them that my MAFs were no good.
The dealer replaced the sensors and the housings with original BMW parts, all free of charge to me.

KBK · 26th May 2006, 17:54

Consider going for new spark plugs too. The fuel flow issue has worn the plugs down a bit.