Weird Idle issues

[manolobonz]

Hey guys, my car just suddenly gave me weird and annoying idling issues a few days ago. My car is a '98 E36 316i. Whenever the car warms up, it never idles properly anymore. Say I'm braking to a stop in traffic, as soon as I step on the clutch to stop, the car revs up on its own way above 1000 rpm. It varies, and even revs all the way to about 1800rpm before it slowly goes down, then when it goes below 1000rpm, the idle dips way down to about 400rpm where it seems to almost die down, then revs back up to 1200-15000 rpm then goes back down again and the cycle keeps on going! If it does stabilize, only for about 10 seconds. It revs up again, then dips down, then revs up. You can imagine how crazy this is for me especially on my daily commutes.

What might be the problem? I'll give a little service history on the car as well.
I have a brand new MAF sensor and alternator installed. I had an oil change recently with oil and air filter replaced. I also had the throttle body cleaned which was very dirty inside near where the throttle position sensor was. this helped give my car better acceleration I noticed. I have yet to replace the fuel filter. I had the ICV cleaned about a year ago. I also had it checked for any error codes but none during the oil change about a month ago. The problem just started to occur about 4 days ago.

Where do I go now? Help please

[Javier]

The problem starts _after_ the car warms up you say?

One thing you didn't mention is if you checked on the spark plugs. Maybe is just a simple cylinder misfire due to a faulty spark plug... But if it starts _after_ the car warms up then it probably is not due to that.

Your 316i has a 4-cylinder engine... 1/4 loss of power is very noticeable. Specially at idle.

[manolobonz]

I forgot to mention I just recently changed my spark plugs also. So that leaves it out. I think i have a vacuum leak.

[manolobonz]

Problem solved. I had my fuel injectors and ICV cleaned out. Good thing there was no vacuum leak! Night and day difference now with my idling. Thanks!