my car has been idleing weird for a few weeks now. after it's warm and i come to a stop light or stop sign, the rpms will drop to about 1200-1500, stay there for a few seconds, then slowly work it's way under 1000 to where it normally idles around 700 or so. it's not setting off the check engine light so i don't have anything to check. i looked to see if the throttle cable was sticking, but it snaps right back into place no problem. the only thing i can think of is i changed the clutch like a week before, could that be doing it. it's a centerforce dual friction clutch and pressure plate with the centerforce throwout bearing (if it means anything to you). is there anything else i should take a look at? thanks in advance.

 

I have litte experience with TBI, but...

on my TPI setup, I have a sensor called the IAC (Idle Air Control).
When mine was full of carbon and compressed (really not a good thing), the car would idle poorly and the tach would jump. But when I drove down the road it wasn't bad. This sounds similar to what you are explaining.

More than likely, your TBI has this sensor or one similar. I would check it to make sure it is not compressed and/or full of carbon.

I believe, for TPI, you can buy a new one at Autozon for about $50.

Hope this helps.

 

I agree, sounds like what my TBI s-10 did, it threw a code for the IAC after it got really bad. Price was around $50 for the TBI unit too.