E30 Zone

First time posting so let me know if I have done anything wrong.

Having issues with my 1988 318i, when I start the car cold it will idle at 500-600 RPM and when warm it will idle at around 1000-900 RPM, trouble is when it's cold and idleing low it will stuggle to run and try to stall, it will also hesitate when you press the throttle down which makes it a pain to drive. It feels like th idle control valve isn't working right but can't figure out the issue.

So far I have changed the blue temperature sensor and get the correct readings at the ECU, I have reset the throttle position sensor and idle stop valve and also get the right readings at closed throttle and WOT at the ECU, checked for air leaks and can't find anything I have replaced the fuel pump and still can't get the cold idle RPM up. Took the idle control valve off and can't hear it buzzing with ignition on which apparently it should, when I crank the engine over the ICV closes all the way shut which I thought it should open the allow more air and increase the revs.

Can anyone tell me how the idle control valve should work, when should it be open and closed inside and how much should the window inside open as mine currently will only open a small amount, it's either fully closed or a quarter open which doesn't seem enough, will try to attach some photos of the ICV.

Willing to try anything now to get the cold idle up and running a bit better.

Welcome to the zone mate, your in the correct area and nothing wrong at all !!!
I`m sure guy`s will be along to help you but in the meantime ...........lets have a load of pic`s of the e30 please ?

Mart.

Don't have many up to date photos due to the rubbish year we have had so got some old ones when I first bought it and a couple from a rainy Silverstone classics show when I last went, hoping to get her back out to some more shows soon

My M40 had idle issues also. I fixed all the vacuum leaks and still couldn't get it stable. I was trying to avoid replacing the Idle Control Valve because of the high cost. But, when I found a new one on amazon for $30, i just bought it.

Idle problems solved!

Here's the location:

When I've problems with idle control valves in the past, I've just rinsed them out with brake and clutch cleaner and that's always done the trick for me!
They tend to get clogged up with carbon deposits etc and you'll be amazed at how much crap comes out of there with a good clean. Just get yourself a can and give it a try! Worth a shot for a few quid on a can of spray and it might just loosen up all the crud out of there and get your i.c.v working again!

Good luck and please let us know how you get on

boiliebasher wrote: ↑

Mon Feb 22, 2021 3:03 am

When I've problems with idle control valves in the past, I've just rinsed them out with brake and clutch cleaner and that's always done the trick for me!
They tend to get clogged up with carbon deposits etc and you'll be amazed at how much crap comes out of there with a good clean. Just get yourself a can and give it a try! Worth a shot for a few quid on a can of spray and it might just loosen up all the crud out of there and get your i.c.v working again!

Good luck and please let us know how you get on

Gonna give it a clean out today and see if that changes anything then try it on the car again, everything seems to be free inside and moving but there doesn't seem alot of movement on the slide window inside, can you remember if your window inside opened up more than my one in the picture? Cheers for the help.

You could remove the air flow boot and clean the throttle body out with some carb cleaner. That can also cause idle issues.