My IDLE SUCKS!!!

[MonkeyM20]

My 325is hates to idle. Its a 1991 with 94k, auto. The car starts fine, but the ide is very rough, and both sounds and feels like a cylinders not fireringat idle. It has new plugs, new cap & rotor. Just had a valve adjustment, clean air filer. I dont know what to do.

When the engine is cold, it will often stall when i put it in gear if im not gasing and braking at the same time. After the first 2 minutes it stops its want to stall. but the idle is still very rough at its 600-700rpm's.
If you take the engine to 1100 rpms it smooths right out and has no touble or problems reaching 6000rpms smoothly with no loss in power.

I have a feeling its some sort of electrical problem. I'd like some help diagnosing it furter before i spend money on something thats not broken!

It usually sits out in the elements, but when it sits in a garage for a few days it seems to idle/run alot better. It also runs better when its been driven for 30+ minutes.

If you need more info Ill reply with it as soon as possible.

PLEASE HELP... its driving me CRAZY!

-Josh

[325ise30]

My 87 "is" has the exact same problem, I still dont know what it is but here is what I have replaced in atemt to solve it

Ecm + updated chip, Idle controle valve, Mass airflow meter, cleaned injectors + ports, Coolent temp sensor, ox sensor, and plugs, wires, cap ect.

I have tested the following, Compresson, fuel press, checked for vac leaks, and tested numerous wires for continuwity.

Well the only thing i havent done electricly is replace the harness or crank sensor. But the strangest thing is if I disconect the ecm or batery 15+mins or so, it will idle normal for about three day and eventaly end up back where it started.
I hope this info gives you some insite into what not to replace, but maybe there is somone out there who knows how to solve this, good luck.

[nando]

check your intake boot, it's probably cracked or has holes by now. clean out your ICV with carb cleaner. replace vaccum hoses. make sure your throttle position switch is functioning. those all make a big difference in your idle.

O2 sensors are ignored at idle..

[MonkeyM20]

thanks, ill start makin a check list. i realy cant wait to get this fixed.

if anyone else still has an opinion please toss it my way. comments and suggestions welcome!

-Josh

[MonkeyM20]

check your intake boot, it's probably cracked or has holes by now. clean out your ICV with carb cleaner. replace vaccum hoses. make sure your throttle position switch is functioning. those all make a big difference in your idle.

O2 sensors are ignored at idle..

How do I check to make sure my throtle possition switch is still working?

[325ise30]

I forgot to mention in my last post that I tested and ajusted my throttle position switch, cleaned the throttle body, checked my intake boot and vacuum hoses. all of witch made no "idle" differance, but performace is normal.

[nando]

check your intake boot, it's probably cracked or has holes by now. clean out your ICV with carb cleaner. replace vaccum hoses. make sure your throttle position switch is functioning. those all make a big difference in your idle.

O2 sensors are ignored at idle..

How do I check to make sure my throtle possition switch is still working?

you need to test it with a multimeter. the bentley describes all of these procedures in detail, be sure to buy one.

I also forgot to mention, adjust your valves. it will idle quieter and probably run better (unless you screw it up).