Idle problem driving me NUTS!!!

[drwambo]

Hi all,

I'm at my wits end. Idle is bouncing from around 600 to 1300 or so in a cyclic fashion. I have cleaned (tons of crud) out of ICV and tested. O2 and ICU appear to be working. Have looked for vacuum leaks and can find none. Yesterday, while checking for vacuum leaks, I pulled the dip stick out. Lo and behold, the idle settled down at about 700 rpm and stayed there. Of course, with the dip stick out, my acceleration went to pot.
It almost seems as if the engine is producing too much vacuum - which apparently is fluctuating enough to induce the cycling idle.

Another interesting note is that there is a whistle being produced by the ICV which gets louder as you throttle the motor up. This to me suggests vacuum leak, but After a full can of carb cleaner sprayed all over, I can't find a leak.

I dont' have any test parts to verify that the tested parts are good, but they all seem to be functioning.

Does anyone have any thoughts? Motor runs great other than that.

BTW-84 325E....2.7L

Help.....

[new2bmw]

I had the same problem...and i fixed it by adjusting the idle air screw. It is located in the air idle which is connected to the valve cover on the right side of the motor. with the car running turn the screw to adjust idle down to around 700 rpm. This will solve you idle problems.

[drwambo]

Thanks for the post. Ultimately, I did the penny trick, which seems to have resolved the problem. Still don't know whether the problem was the ICV or the ICU, but who cares, It's kluged for now!!

On to getting rid of the stutter in my accel. I'm thinking that my CAT may be shot, which might also explain the cycling idle. Guess since we don't have emissions here, I'll just have to remove it!.

Douglas

[Webgecko]

Originally Posted by drwambo

Thanks for the post. Ultimately, I did the penny trick, which seems to have resolved the problem. Still don't know whether the problem was the ICV or the ICU, but who cares, It's kluged for now!!

On to getting rid of the stutter in my accel. I'm thinking that my CAT may be shot, which might also explain the cycling idle. Guess since we don't have emissions here, I'll just have to remove it!.

Douglas

Hi there. I think I may be suffering the same fate as you with the vacuum problem, however, I'm wondering what the penny trick is.

Cheers!

[mahikero]

hi there,
can you pls! tell tell what is ICV or ICU which parts of the engine is that.. pls! explain

[Twinturbo4x4Lux]

the problem is with your idle control valve, it is a common problem on the earlier 3 series, i have had to replace several as i work for bmw, also your hessitation on idle will be caused by the vacum leak due to the stuffed idle control valve.