1991 318i idle problems...

[quebecnic]

Hi everyone, I'm new to this forum since i got my first e30 about 2months ago. I got a good deal on a 1991 318i with 200 000kilo on the clock. Since i got the car, it always iddled pretty badly, when a start the car it get to about 1100-1200 rpm and then it drops to about 800, them 5-600 and then 4-500... Sometimes it even die if i do not give it a little bit of gas. Does anyone have an idea what could be the problem? I replaced the sparkplugs when a got the car so i'm pretty sure that is not the problem...

Thanks in advance,

Nick

[squidmaster]

sounds like icv to me, try cleaning it up or just replacing it. I see a few around the forums for $25, and a few even less.

[Bmr]

Hi everyone, I'm new to this forum since i got my first e30 about 2months ago. I got a good deal on a 1991 318i with 200 000kilo on the clock. Since i got the car, it always iddled pretty badly, when a start the car it get to about 1100-1200 rpm and then it drops to about 800, them 5-600 and then 4-500... Sometimes it even die if i do not give it a little bit of gas. Does anyone have an idea what could be the problem? I replaced the sparkplugs when a got the car so i'm pretty sure that is not the problem...

Thanks in advance,

Nick

sounds like icv to me, try cleaning it up or just replacing it. I see a few around the forums for $25, and a few even less.

i agree with squid i used wd40 on my ICV and it worked wonders. Car idles at 700 now at start.

[quebecnic]

Thanks for the reply guys, i will take a look at the icv and try cleaning it and see if it works! Could it also be the oxygen sensor in the exaust system?

[oldmann]

Could also be vacuum leaks, Most of this stuff is 22 yrs old and original.

Have you done a stomp test to pull engine codes? (search stomp test)

[quebecnic]

Yes i did but the check engine light always on so the codes aren't in memory...

[squidmaster]

No the car should still run fine without any o2 feedback at all (speaking from experience)

[Bmr]

Also check cracks on intake boot after AFM. I also thought bad temp sender would cause erratic idle also. While its running spray carb cleaner around everything on top. Just to make sure you don't have a vacuum leak if it still does after ICV

Sent from my SGH-I317 using Tapatalk 4

[quebecnic]

I did check the icv and it was good. While i was taking it out the car i noticed a few craked vacuum hoses.. I think my problem was there. I replaced the ones i could without having to take out the intake manifold. Since then the idle is way better but when i'llhave a little bit of time i will change the rest of the vacuum hoses and everything should be alright.

[roguetoaster]

If all you want to do is change the vacuum hoses you can route new ones under/around the intake without removing anything more than the airbox/intake boot.

When you did the stomp test to check codes did it not flash anything? IIRC when I had solid CELs in the past the stomp test did show what they were.

[quebecnic]

I got absolutely nothing when i did the test.. I've talked to a bmw mechanic and he told me that i didn't get any codes because my check engine light isn't always on the computer doesn't keep in memory the codes if the check engine light isn't permanent.

[roguetoaster]

I got absolutely nothing when i did the test.. I've talked to a bmw mechanic and he told me that i didn't get any codes because my check engine light isn't always on the computer doesn't keep in memory the codes if the check engine light isn't permanent.

Perhaps your throttle is poorly adjusted and you should try setting the key to on and actuating the throttle in the engine bay by hand to full stop five times. Alternately your throttle position sensor is on it's way out or there is a broken wire at the plug for it, if this is the case pulling back the boot on the TPS plug will generally reveal the break.

It's also been my experience that when I have a non constant CEL I can get it to flash a code, if I do the test soon after I see the intermittent CEL.