Idle problems??? Only when cold

[LE30]

Hi,
I have a problem with my 1989 BMW 325i(mechanically stock).
Here's how it goes, when I start the car when the engine is cold it will idle fine for 3-4 seconds and then it will jump up and down from 800rpm to 3500rpm. When I accelerate the car will kinda junp around until you hit a higher rpm. It will continue to 'idle where it wants' until I've been driving for 10-15minutes(a fair bit of time after the engine is warm)

I was thinking it has something to do with the cold start valve or something. Or it could be the fuel injector cleaner I put in the tank(it was free and i thought it may help). Also, soon after I put the fuel injector cleaner in the fuel pump broke and ever since then it's been acting up.???

Any suggestions or help is gladly appreciated.

Thanks

[prb44t]

I would clean the ICV (Idle Control Valve) and the MAF. When the car is cold and the idle is jumping take a screw driver and give the ICV a quick tap and see if the idle settles. Sometimes a little dirt gets stuck in the valve and prevents it from opening and closing as needed. A light tap sometimes loosens it up.

[E30_fiend]

^^^^^^
our cars dont have a MAF and I would suggest cleaning the AFM(air flow meter) with carb cleaner or MAF cleaner. It should be fine.

Clean the ICV though. If its cold out, the valve might be getting stuck til it warms up after driving for a while






Taylor

[LE30]

Ok, I will do that. One thing is that it doesn't matter how hot or cold it is outside it will still do this. We'll see
Thanks

[LE30]

Ok so I cleaned the AFM with carb cleaner and the idle stabilizer valve is fine(took it off a working car). It seems to run better but it still jumps around and the rpm still goes from 800 to about 2800.

I don't believe there are any vacuum leaks(have done a few tests) so I'm really wondering what it is. Fuel injectors? I also changed the spark plugs today and they were all the same except #1 was brown and not white.
Could it be that fuel injector #1 doesn't squirt right until its warm?

[downernsp]

Have you checked your tps

[dmwe30]

tps n cts r the first things id check

[downernsp]

What about temp sensor??

[Quailane]

What about temp sensor??

Yeah, that might be an issue but it is hard to check as the resistances to the temperature are not well given and are pretty broad.