Secter

Hey guys,

A few months ago, I noticed that when I push in my clutch when making a stop, the RPMs drop below 500. It sounds as if the car is about to die when it does this. However, it will idle down in the 500 range then shoot up to ~1k where it should be. I imagine this is the computer adjusting because it catches the problem. I haven't made any type of changes to the car for well over a year. I tried to see if a reflash would help, but it didn't seem to do anything. When I did this, I pulled the terminals off the battery for about an hr, reconnected them, and reinstalled the Brenspeed tune I have. While driving around shortly after, I still have the same problem, if not slightly worse. Generally, it seems to be worse when the A/C is on full blast versus off, but it still does it with the A/C off. I really would like this to go away.

Any suggestions???

AmericanSpeed

I got an erratic idle after I had the lightweight flywheel installed, and it only happened when the AC was on. I just added some revs at idle with the SCT and it helped out tremendously. I added 40 rpm (from 750 to 790) which is one notch with the SCT since it adjusts at 40 rpm increments.

Secter

I just checked my tune, and the Idle RPM Driving and Idle RPM Neutral settings are both 850. If I am at a complete idle (parked, clutch out, gear in neutral), the car idles with the A/C on and off just as it should. I will sit at that 850 mark all day long. However, once I start driving and get the car in gear for a second or two, the moment i push the clutch in and let the RPMs fall, they drop down to about 400-500. After a few second of sitting in the 500 range, it will kick back up to 850-1000. I read that this could be due to a MAF or IAC issue, however, the people saying that could the problem had much more serious issues it seems. For example, their cars would actually die when the RPMs dropped so low. Fortunately, mine has never done that but I don't want it to happen either. This is why I need to try and get this resolved.

Could the Texas heat possibly be an issue here?

hammeron

i liked americanspeeds idea, but since
you say your rpms are already set fairly
high, we need to look elsewhere.

at first i was thinking charging system, but
now am leaning toward:

clean the MAF
clean the throttle body

Secter

Thanks hammeron, I'm gonna take out the CAI completely and make sure everything is clean up to the TB tomorrow.

GidyupGo

Maybe the clutch isn't completely disengaging and there is a slight draw on the engine.

hammeron

excellent point....

if there is a big difference between
pulling up to a stop light, clutch in and
in gear (more drag), versus clutch in and in
nuetral (less drag), it could indicate a clutch
related issue

llamatymer

Hey all, i'm not sure if the 3v's have IAC Valves, but if they do, and you have a rev mod it might cause that though i'm not too familiar with the 3v's. Just out of curiousness do the 3v's have problems with hanging rpm's like the 2v's?

Thanks,
-Matt

hammeron

hey matt, i havn't read about any
(3V) hanging rpm problems, but i think
a vacuum leak would be the most
likely cause, if it were to happen

moosestang

That's possible, but i'd expect the car to try to roll forward. My bet is a dirty throttle body or IAC sensor. Do these cars have a IAC sensor?