unstable idle, and jerky cruising

[Thin Air]

I have a 97 328is. Since I've had my M3 cams installed my car idles weird, and when cruising it's pretty jerky.

Before I had the cams installed I had a slight raising and lowering of the rpms when the engine was cold, which I would just assume it was my ICV. But now I've had it a couple times where I start it when it's cold, and I start it, it holds at 900 rpm, but it feels superly lumpy, like something is misfiring. When I'm cruising at any speed or gear, it gets jerky, but as soon as I get a bit on the throttle it goes away. Under full acceleration no problems are noticable.

I tested all my ignition coils and they all read 0.8ohms, which I'm told is normal. I thought it might be my fuel filter, but if it was that clogged it wouldn't be smooth under full throttle. The spark plugs look ok.

I've had one person say it might be the vanos, and that the 328 and M3 vanos' are different, although there a a bunch of people with 328's with m3 cams with no problems.

As a note, I also have an m50 manifold, AA m50 manifold software, fan delete, asc delete, underdrive pullies, and an ltw flywheel.

[Thin Air]

nobody?

[e36]

i had a similiar problem on my 92 318........between 2500-3500 rpm it would go outta wack.....turned out to be the crank sensor....search the forums under "surging, sputtering, irratic" behavior.....if i find the thread ill post it
________
mercedes-benz u.s. international

[JonVanderArk]

I was having that with mine. Head is cracked. Don't wait to go in and get it checked!