Author Topic: Idle issue after cleaning IVC *With Video (Read 2952 times)

Windsma · « **on:** October 09, 2009, 10:52:59 PM »

I replaced my intake bellow, IVC hoses, fixed the valve cover bypass vent tube

then put the intake all back together.
(M42 4cyl)
now i have this erratic idle issue. It bounces from 1500 to 2000 -1500-2000-1500-2000
IDK if the computer had to be reset or if i need to start pulling the intake again.

where should i start looking?
sounds like a vacuum hose is off?

http://www.youtube.com/watch?v=a3WlPlmWTGw

Ramblin MAn · « **Reply #1 on:** October 09, 2009, 11:04:16 PM »

I know exactly what that is.

Your idle control valve is stuck wide open or you have a major vacuum leak.

The reason it fluctuates like that is because your computer sees that your rpm is too high as compared to what the TPS value says it should be reading so it shuts off the injectors for a few revolutions and then turns them back on.

Give your ICV a whack with the handle of a screw driver and see if it drops. Also, if you (or someone) turn on your ignition you should be able to feel the ICV vibrate in your hand. If it's not........

Windsma · « **Reply #2 on:** October 10, 2009, 07:48:14 AM »

Great, THANKS!

I have the E36 so its a little harder to get to but you put me in the right direction.
It was working ok until i removed it. I hope i dont have to buy a new one ($100)

Windsma · « **Reply #3 on:** October 10, 2009, 06:38:27 PM »

So i have a bad ICV

It must have been stuck closed before and when i cleaned it.... it opens at the wrong time.
Is it possible to plug it up backwards?

Unplugged maf idle went crazy
plugged it back up
pinched off the valve cover bypass hose (bc before i replaced it it was crimped)
nothing changed.
Unplugged ICV......

back to normal.
Idle is about 1200 (high i know now but, thats the way its been since i bought it.)
Ill try to find a IVC at the local upullit monday.

When the IVC was erratic i drove it down the street. It had a lot more power and felt like i finally got WOT. I hope this will help my acceleration after i replace it.

Windsma · « **Reply #4 on:** October 22, 2009, 08:46:33 PM »

I havent found a ICV yet.

The Idle has recently started to bounce from 1000-1200 (after letting my father borrow the car)

Im going to remove the intake tomorrow and look for anything.....

Ramblin MAn · « **Reply #5 on:** October 22, 2009, 08:59:10 PM »

I know this is kind of useless, but turn on your AC and see if it gets better or at least steadys out a bit. When you turn on the AC the computer tells the the ICV to open a little to compensate for the load from the compressor. A lot of times that will stop the bouncing. You will still have the problem though.