Cold start / idle problems... please help!

[evil-diesel]

Hi everyone,

My 83 323i Euro has developed a cold start problem which i can't figure out. The car only has about 75k Miles on it and it is in great condition overall.

Here's the Problem:

1st try:

-Car has been sitting, engine is cold
-Ignition turns right over
-Engine cranks
-I let go of the key and it will die right away

2nd try:

-I turn the key again
-The only way to get it to keep running is by applying the throttle for a couple of seconds.
-This results in a lot of smoke coming out of the exhaust
-The engine will now run extremely rough for the first couple of minutes
-The power seems to not be there completely
-The engine sounds weird

After a couple of minutes the engine comes alive and runs perfectly and sounds healthy. The only thing out of the ordinary is that the idle is above 1k for quite some time until the engine is truly warmed up.

Now on to the idle:

Once the engine has heated up, the idle drops down to about 750 - 800 rpm. The problem is that once the idle has gotten to this point, it will keep fluctuation up and down by about 50 rpm. It just keeps bouncing up and down steadily.

Can anyone help me out with this?

[Click]

What's your engine management, L-Jetronic?

[JrCamacho]

sounds like an AFM problem.. but im not sure. My 318is did the same thing before it went bye-bye, however it would never hold idle unless i slowly let off the gas pedal towards idle.. and even then it wasnt 100%

[EThirty318i]

I don't think it would be your AFM, you can start the car with out it on the car or unplugged and it will still idle. For the idle, I want to say its your ICV. To test it, take it off the car, unplug it, and shake it. If you hear something moving inside, your good. But, if you hear nothing at all, its bad. The ICV helps with cold starts- until the motor is warm. and from what you've said once it idles for a little it sounds great and idles right. So IMO its the ICV.
hope it helps!

[JrCamacho]

AHHH thats how my brain is functioning this morning, totally meant ICV!!

i need coffee/caffeine

[evil-diesel]

I don't think it would be your AFM, you can start the car with out it on the car or unplugged and it will still idle. For the idle, I want to say its your ICV. To test it, take it off the car, unplug it, and shake it. If you hear something moving inside, your good. But, if you hear nothing at all, its bad. The ICV helps with cold starts- until the motor is warm. and from what you've said once it idles for a little it sounds great and idles right. So IMO its the ICV.
hope it helps!

thanks for the insight... I'd like to try fixing this myself by trying to clean the icv before i replace it with a new one... it there a DIY writeup somewhere?

Also, the car will run great once it warm up... but the revs will bounce up and down during idle, and the car sort of shakes or shudders as the revs go up and down in idle... any ideas?

[scrowner]

You do not need to remove the ICV to check it. When you do get the car running, simple place your ear close or even place you hand in the ICV. It should vibrate if it is functional. You have a year earlier car than what I am used to but it should work the same. Disconnecting the ICV from power should result in a roll of about 1-2K RPMs up and down. At least you should see a noticeable difference in the operation of idle with no power to the ICV.