rough idle + engine stalling

[deca]

Hey guys,

I’ve owned my E30 for a while now but fairly recently I’ve been encountering some problems. First off, when my engine idles it sits at 800rpm, then automatically revs up to 1.2-3k, then drops back down again to repeat the process. Additionally, on occasion the car will just stall when I’m driving it. I’ll be driving at 3-3.5k RPMs, then I’ll just lose all throttle response and the car dies - sometimes I get lucky and the car won’t totally die and will come back to life after pressing the gas pedal with nothing happening. When I stop at a light on occasion the car will just totally stall, then have a hard time starting back up.

Besides that the car runs & drives perfect, should I just clean my ICV? Or does this sound like something more severe? Thanks.

[Sonny]

rough idle + engine stalling

How’s the tension on the throttle cable? Mine was loose as all hell.

Turn off car and have someone floor the pedal, does the throttle lever move all the way to the end just like when you push with your finger?

I bet your air intake elbow is torn or something in there is loose and not clamped tight enough that creates gaps to loose vacuum at certain situations, stalling the car.

Start car and wiggle the entire air filter housing and air intake elbow and see if the car dies when you shake and perhaps create an air gap , if there is one.



Last but not least pull the brake booster vacuum hose, the car should die. if car stays on you probably have a huge vacuum leak somewhere and the car is already compensating at idle. Don’t know how accurate this test is but worked for me

[deca]

How’s the tension on the throttle cable? Mine was loose as all hell.

Turn off car and have someone floor the pedal, does the throttle lever move all the way to the end just like when you push with your finger?

I bet your air intake elbow is torn or something in there is loose and not clamped tight enough that creates gaps to loose vacuum at certain situations, stalling the car.

Start car and wiggle the entire air filter housing and air intake elbow and see if the car dies when you shake and perhaps create an air gap , if there is one.



Last but not least pull the brake booster vacuum hose, the car should die immideatiely. if car stays on you probably have a huge vacuum leak somewhere and the car is already compensating at idle. Don’t know how accurate this test is but worked for me

I will definitely try that out.., but now that I’m thinking about it, I did replace the air filter a few days ago and don’t think I did it correctly, even though I got the right air filter (exact same size as the old one) I struggled to fit it back into the air filter housing, so I just kinda stuffed it in there and clamped it down and thought to myself that I would come back to it later as I had something else to do at the time. Crossing my figures it’ll be that, but regardless I really appreciate your help!

[Sonny]

rough idle + engine stalling

I will definitely try that out.., but now that I’m thinking about it, I did replace the air filter a few days ago and don’t think I did it correctly, even though I got the right air filter (exact same size as the old one) I struggled to fit it back into the air filter housing, so I just kinda stuffed it in there and clamped it down and thought to myself that I would come back to it later as I had something else to do at the time. Crossing my figures it’ll be that, but regardless I really appreciate your help!

Take everything off and retighten it all, everything you touched to do the air filter. It should just the air box that houses the air filter. Do it now Before you kill your engine from dirt or yourself from loosing power while in motion.

[deca]

Take everything off and retighten it all, everything you touched to do the air filter. It should just the air box that houses the air filter. Do it now Before you kill your engine from dirt or yourself from loosing power while in motion.

Will do, luckily I’ve barley driven it since I switched the filter (just around the neighborhood so the car doesn’t just sit for too long). Thanks again the the advice :)

[Gregs///M]

Check your throttle position sensor but the most likely issue is a vacuum leak.

[deca]

Check your throttle position sensor but the most likely issue is a vacuum leak.

Ah, I see. When getting out of my car today I found a small wire on the ground under my pedal box? Could that be the issue? I’ll attach a photo of the wire I found below.

https://imgur.com/gallery/7XaqVbi