High Idle

[Glliw]

Ok, so it has been a long time since I've posted on here, but I haven't really had the need since I got out of DSMs. Buuut, my friend has a wonderfully crappy 97 RS that needs some TLC. Besides the overheating issues I've been fixing, the idle is out of control. At first start up it will idle at about 1000-1100. After driving, especially on approach of a stop light after popping it out of gear, it likes to hang anywhere from 2k-4.5k. I figured the tps might be out of whack or the BISS screw, but after looking at it, the 420a doesnt have a biss or adjustable TPS? What could this be?

 

[jakop92]

It should have one. Right on the throttle body by the intake manifold. It might have fallen out.

You can buy a new one at a mitsu dealership.

 

[Glliw]

Yea, I could've sworn they had one too. But I looked and didn't even see a recessed area for one to be at. I know the '63's have them there, I fought with mine alot when I had mine.

 

[jakop92]

It has to be in there somewhere man. Or else it fell off. I am pretty sure it has to have one. Should be on the throttle body somewhere.

 

[Glliw]

yea, 2.0l 420a, no turbo. Just factory POS. I swear I'm not blind but I'll look again tomorrow....

 

[jakop92]

You must be logged in to view this image or video.

Thats the only picture I could find of that TB. I don't see it anywhere. Its the only picture I could find man.

 

[Glliw]

Yea man, that's what I'm saying. Does your car have the factory TB on it? If so, could ya pic me it?

 

[jakop92]

Yes I have factory TB. You have to take in mind that I have a spyder gs though. It has a 4g64 engine in it, not a 420a. Should be pretty similar though.

Here are pics:

You must be logged in to view this image or video.

You must be logged in to view this image or video.

 

[Glliw]

Ok yea, your's is completely different . I need to find someone with a Neon and mooch off of their car I guess.

 

[jakop92]

The first pic that I put up is the only one I can find. I can't find ANYTHING else. Sorry I can't help, but good luck!

 

[EagleTSIawd]

have you checked for any vacuum leaks? those can cause some weird idle problems

 

[Glliw]

I did, and I really couldn't find any. The intake is on there tight,with the PCV going back into it, there is 3 T's on the IM that are nippled off that I am assuming are for the Emissions.

 

[EagleTSIawd]

...hhmm, how about and try this... when its idling that high open the hood and try and hold the butterfly shut, if the rpms go down then the cable is too tight

 

[Glliw]

Yea, tried that, I even adjusted the throttle cable bracket all the way to the loose end to no avail. It doesn't seem to be binding anywhere. It seems non-mechanical to me.

 

[EagleTSIawd]

no biss screw, no vacuum leaks, cable is not tight... crap, im out of idears. Unless, base timing??? oh wait, u cant adjust the base timing on that car can yah... then again, ive never seen a car idle that high because of bad base timing... dont know dude, its the dsm curse

 

[Glliw]

Yea, that's what I'm saying unless some sensor has completely ####ed itself. Does the MAP have anything to do with this?

 

[EagleTSIawd]

if any sensor went crap, then you would get a CEL light. Theres also the Fuel Pressure Regulator, if that goes bad you wont see a CEL, the car will run like crap though... im not sure if that would cause the symptoms you are having... you could check it if you have a pressure gauge, i think there is a place where you can screw it on the fuel rail

 

[Glliw]

As far as fuel pressure, the car pulls "hard" to redline so I don't think that would be it.

 

[EagleTSIawd]

I was browsing around and i found this thread, i hope it helps you solve out your problem

check it out
http://www.dsmtuners.com/forums/420a-bolt-tech/270965-seems-like-iac.html


let us know if it worked out

 

[Twistaye]

I was about to pop in and say something about the IAC or ISC whichever you want to call it being the culprit. We *had* a 93 dodge stealth (before it got totalled) and the ISC went bad, the car would idle 1500 rpms in neutral and around 1300 rpms in gear (automatic tranny). Turns out the ISC was out of adjustment, we simply turned the screw on the inside of the cover counter clockwise and it worked fine after that, of course until my dad got drunk one night and decided to go drive it. 7 broken ribs, mild concussion, 68 days in the hospital, 7 tickets in one and a couple other things later the stealth is no more, oh well crappy non-turbo version ! The ISC on the 4g63 and the stealth engine were actually the same so I would try that out