well now between 2 diff. mechanics no1 can find anything wrong w/ my car thats making it idle..it drives fine and everything its just at idle its like pulsing instead of bein smooth..but like its noticeable, not horrible tho...my timing belt was changed but i got that checked and its all aligned right, i just put a used ECU in it and it was doin it after..but i had problems before so it was doin all kinds of stuff before 2...im gonna guess its either a vac. leak, exhaust leak, or somethin w/ the ECU, but how do i check?


Mods: E-bay Intake, Vibrant Muffler, J Woodleys Ground Wire Kit, F&R Upper Strut Bars, B&M Short Shifter

is it the right ecu?

1995 Eclipse RS

I have the exact same problem. I put a new ECU in, and it did the same thing. Try buying an ISC (Idle Speed Control) or IAC (fancy name) from ebay. It should fix your problem

i forgot to put that its throwin out CEL's 12 and 31..is there any way to check my idle speed control b4 i buy 1?..i already put alotta money into it in the last month and i dont feel like putting more if i dont have 2

Mods: E-bay Intake, Vibrant Muffler, J Woodleys Ground Wire Kit, F&R Upper Strut Bars, B&M Short Shifter

When you buy one, make sure it's for the right motor. 96, you bought one for a 4g63.

There might be a procedure in the Haynes manual for checking the resistance and stuff. You can take the IAC out and clean the pintle to make sure it's not interfered with. Although, I'd be more suspicious of a vacuum leak. Any hissing you can hear around gaskets/O rings?

Brian

Red 97 Eclipse GS (420a) MTX
Custom Garrett T3 Turbo system
Megasquirt w/52 lb/hr injectors & a Walbro 255
Kicker/Alpine Audio (3 amps, 2 subs)
90 Cav 2.2 TBI auto (winter) <- yeah, it's fast

You can check for vacuum leaks by spraying carb/choke cleaner (or another flammable substance) where gaskets are (between the throttle body and upper intake. If you spray it all the way around it and the idle jumple a little bit, bingo. You can also try it where the upper and lower intakes are bolted together, as well as where it meets the head, around vacuum lines, you get the idea. Just make sure you've got a fire extinguisher handy just in case.

It worked for me on my bike when I was trying to find the vacuum leak.

~Luke
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1969 Cougar - 11.91 - 380HP
2007 GSXR 750
1999 OZ - SOLD - 15.26 NA - 14.71 on 75 shot

well i dunno if i really wanna spray shit all over the place when i dunno what im doin lol...i heard u can use a smoke system and the vacuum leak would suck it right in if theres 1 there...can i just lite up a nice big cigar and try that?...and no i havent heard any hissing;would it be noticeable or would i hafta put my ear right up 2 it?

edit- i just called my mechanic that checked it over to see what it could possibly be besides the timing belt and he said he checked the entire car for vacuum leaks/exhaust leak/ALL sensors, and everything there is to check besides the internal parts..soo i dunno what to do w/ the dam thing lol..i think im gonna get a GST muffler just so i dont hafta listen to it all the time


Mods: E-bay Intake, Vibrant Muffler, J Woodleys Ground Wire Kit, F&R Upper Strut Bars, B&M Short Shifter

did you just get your timing belt done?

You can be a tooth or so off and it will drive fine, but your idle will sound lopey.

Sounds like your prob.



Nick
97RS


THX KAPTAIN MYKE FOR HOSTING! www.kaptainmyke.com

connect a vac gauge to a vac source on the intake. At idle, it should be between 17-20 hg's of vacume. If its lower than this, like 10 or whatever, then your timing belt is not set correctly. I would do this first, just to rule it out, and it very simple to do. The timing belt being off just one tooth, can cause exactly what you are describing. A crappy idle, but off idle it runs fine..

13.5 @108 MPH-2.2 60ft(stupid FWD!)
S16G @ 18 PSI/FMIC/Running on MegaSquirt II (Now with sequential
fuel injection)
My webpage: http://eclipsed4evr.home.comcast.net
-1998 Mitsubishi Eclipse RS-T- "Toy"
-1992 Plymouth Laser Turbo AWD(SOLD)
-2000 Honda CR-V(daily)

yea it was changed and i took it back to him today and he said it was fine...im gonna try to vacuum gauge that sounds pretty safe lol...if its not that im just gonna let it run how it is and not worry about it..im hopefully gettin a new car by the end of hte summer anyway..im puttin my POS in my backyard and just rippin her apart and havin a lil fun lol..oh and he cleared the codes 12 and 31 so right now i have none..which makes my gauges look kinda naked


Mods: E-bay Intake, Vibrant Muffler, J Woodleys Ground Wire Kit, F&R Upper Strut Bars, B&M Short Shifter

i also forgot 2 add that it only does it after its warmed up...when i start the car it runs fine (idles around 1200 then goes down like it should as it warms up)..once it hits under 1000 it drops right down to 700 or so and starts pulsing..going between 700-900...i dunno if that would mean anything

edit- im also getting a lil worse gas mileage (im gettin around 25-26, last time i did it i was gettin like 32)..and every once in awhile (once a day or so) i can smell the CAT burnin, which i think would coincide w/ the gas mileage problem..i just dont know whats causing it