Bouncing Idle? - BMW Forum

'85 318i · 03-11-2004, 08:55 PM

So my car Idles correctly most of the time. Sometimes it has this bouncy idle, up down up down up down. Doesnt affect performance, just annoying.

ghead What causes this, how do I fix it? Thnx in advance.

Fox · 03-11-2004, 09:22 PM

Take off your ICV and spray a crap load of WD-40 in it.
or if that doesnt work, check your o2 sensor. There are many others but thats all that immediatley pops to my head.

'85 318i · 03-12-2004, 09:28 AM

right on, it may be the O2 sensor, i been needing to get one... thanks

89325is · 03-13-2004, 03:39 PM

Quote:

Originally posted by Fox@Mar 11 2004, 11:02 PM
Take off your ICV and spray a crap load of WD-40 in it.
or if that doesnt work, check your o2 sensor. There are many others but thats all that immediatley pops to my head.

I have a similar problem... but how do I remove the ICV?? there are at least 2 hoses attached to it.

Fox · 03-13-2004, 03:44 PM

the hoses just pull off. Its not difficult at all. theres no liquid or anything in them so just give them a yank (after you loosen the clamps of coarse)

89325is · 03-13-2004, 04:14 PM

Quote:

Originally posted by Fox@Mar 13 2004, 05:24 PM
the hoses just pull off. Its not difficult at all. theres no liquid or anything in them so just give them a yank (after you loosen the clamps of coarse)

That easy, huh?

Okay, before I try this, is there any trick to putting the hoses back on? I'm guessing that it's a lot harder.

Also, how do I remove/loosen the rubber or plastic clamp (looks like a belt) over the middle of the ICV? I tried loking beneath it, but couldn't figure out how to take it off.

Fox · 03-13-2004, 05:01 PM

its either 1 of 2 types of clamps. its either the type that you unscrew and the band loosens or its just the type that is just bent together. Either way its easy to get off and just as easy to get on.

alanh · 03-13-2004, 05:18 PM

yeah it is pretty easy to get it out like they said, but you may need to replace it instead. mine was busted

89325is · 03-13-2004, 05:33 PM

What about the hoses? Before I take them off, I want to make sure they slide back on easily. Do I have to lube them before trying to put them back on? Or do they just slip on easily? thanks

Fox · 03-13-2004, 05:37 PM

they slip on pretty easy. Shouldnt have to lube them or anything

e30 dude · 03-14-2004, 02:28 AM

i have the exact same problem. the idle fluctuates, and if i let it idle long enough, it will eventually stall. i have an 83 320i (euro), and it doesn't have an O2 sensor or an ICV!! (at least according to the haynes manual i got) so what can be the problem??

Fox · 03-14-2004, 10:15 AM

yours is carborated then. (?)

Spray some carb cleaner through it.

'85 318i · 03-14-2004, 02:48 PM

WD-40 in the ICV worked like a wonder. thanks guys

89325is · 03-14-2004, 07:09 PM

Quote:

Originally posted by Fox@Mar 13 2004, 06:41 PM
its either 1 of 2 types of clamps. its either the type that you unscrew and the band loosens or its just the type that is just bent together. Either way its easy to get off and just as easy to get on.

I just looked under the hood again, and I'm having a had time taking off that belt/clamp around the middle of the ICV. It's a hard plastic strip that wraps around it, and the two ends of the strip come together and are held together by a couple of square-head screws(?). I don't know if they just pull off what what.

If I knew how to post my pics, I'd do it to show you what I mean. I just want to be able to remove my ICV. thanks

e30 dude · 03-14-2004, 10:39 PM

Quote:

Originally posted by Fox@Mar 14 2004, 11:55 AM
yours is carborated then. (?)

Spray some carb cleaner through it.

not carb. i have 320i, with m20b20 engine, L-jetronic, i think.. there's a picture of the ICV in the haynes manual, and when i looked at my engine, that ICV is not there!! and O2 sensors are only for motronic, i think.