On Alfa number 15
AO Platinum Member
Join Date: Dec 2005
Location: United Kingdom
Re: V6 vibrates slightly while idling
My TS does it slightly, the revs go up and down by about 50rpm evey 15 seconds or so.
I don't think its too much to worry about, if it was a lambda or maf sensor it would probably have failed the emissions check, which it passed with flying colours.
It could be a sticky idle control valve, but this often causes the car to stop all together.
It may also be worth checking for air leaks, after the MAF.