idiling problem when about to make a stop.

[M3Jokster]

Hey u guys, help me out here. I have a problem, everytime when i'm about to stop my car at a light, I place my car into neutral and let go of the gas (let car coast to the "stop"), then breaked. I noticed right after I placed my car into neutral, my RPM fluctuates anywhere between 300-1200 RPM, up and down, up and down. My gas pedal is not stuck. I checked that already. My engine does not stall but it feels like it's gonna stall. but when my car completely stops, the RPM stops fluctuating goes back to normal around 700-800 RPM. Any ideas? I have a 95 M3 5-speed with 62K miles. this happens before and after my mods (intake and chip ECIS). so it can't be my mods......I'm hoping to see if any of guys experience this......it's bothering me. Any advice is appreciated.

[SlickM3]

A couple of days ago, I posted this for CYang, who had a similar complaint.

I noticed similar "idle hunting" behavior in my 97 E36 M3 coupe, after cold weather arrived. The symptom only appeared when coming to a stop, after having the engine in various cruising rpm ranges. When I'd approach stop, and let completely off the accelerator, the engine would go to normal idle speed, then briefly dip 500 lower, then come back to normal idle speed.

I asked a $tealer mechanic about it, and he commented about a sticking idler valve, and gave me a free can of BMW fuel system cleaner. I seem to recall that he said he'd only seen this behavior in M3's (????)

I ran the cleaner through, and occasionally run some cheapo Techron injector cleaner... like maybe every six weeks or so. I don't have the idle hunting problem anymore.

My car also got the cold idle software patch from the $tealer. I think it helped shorten and smooth the warm-up cycle. Here in TN, some mornings are about 28 degrees. I start the car, wait one minute, then slowly take off. Idle is smooth very quickly.

Maybe that's all your car need?

[jww///95]

There is nothing you can do about it,

This is from a post i made a couple days ago....




As to the idle problem with your '95, i have experienced the exact same thing, and according to an old post by jim conforti, the ecu on the obd1 cars will not activate the idle circuit controls until below 1.4 mph. That is why when approaching stop signs and other deceleration at idle, the car's idle will "bounce". If your car is anything like mine it will stop after you come to a complete stop (i.e. under 1.4 mph). It's a real pain in the ass, but something to just live with on the obd1 cars because the only solution is to reprogram the computer to go into "idle" mode at a specified mph greater than 1.4, but i am sure that would create other problems or bmw would likely have addressed it.

[M3Jokster]

thanks guys, i thought i had the only problem......I'm not the only one out there.....I thought I'm gonna loose my mind bc of this....... thanks again.

PS any u guys no of any BMW autoshows coming up soon in S. Cali?