Just purchased a 2007 328i Coupe (CPO). This is my fourth BMW and the car is fantastic in all areas except for one - when waiting at a traffic light, the RPMs drop to about 600 and I can feel the car's idle/vibration through the drivers seat and the stick shift knob noticeably shakes. Is this normal? Should I look into having the idle setting adjusted? Thanks.
My 2007 335i coupe used to do the same thing until I put a bottle of Chevron Techron in last November. From what I read in Roundel and Bimmer, this or BMW fuel additive should be used on a routine basis as most gas, name brand or not, is dirty. I see that Texaco now has Techron in its gas, but all the Texaco stations locally have closed or changed brands.
I had our 2008 328i Touring in for scheduled service and mentioned a similar rough idle. Diagnostics showed faults with the camshaft sensor.
It's the ethanol ninja in your engine! It really sucks that useless ethanol is now being mixed in all gas types. Our fine engines are made for this crap, but we are subjected to its use whether we like it or not. It's a mad plot to slow the BMW Cult! ATTENTION!!!!! ATTENTION!!!!!!! Please watch for the high % of ethanol in you gas. It will kill you engine and BMW will not do anything about it!
Of course, every gas station now has "up to 10% enthanol", so there isn't any way to avoid it. Nor is there any way to know exactly how much is in there....short of getting a lab analysis.
Stick with Top Tier Fuel and put BMW's valve cleaner in every 5k miles or so. http://www.toptiergas.com/ There is another thread on this topic.
