weird idle problem!

[peypey's ride]

Ok, I am not new to this site, had a profile for years then deleted it, and I am not new to DSMs. I have a 95 GSX the I built up myself.

The problem: When i start the car it wants to idle ok for a few seconds then it will run up to about 2500 to 3200 rpms and idle there until the water temp comes up to 170 to 190 degs. It doesnt surge like the common idle surge problem, its stable. I have checked my IAC and used different ones only to have the same problem. I have also replaces the coolant temp probe, same thing. My timing is set at 5 degs. Now the timing obviously goes up to when its idling like this until the water temp comes up, then its around 7 to 8 degs timing, good. I even tried playin with my AFC to get it into control, with no luck! Replaced the thermostat. Checked my CAS to make sure it was good and even switched out to a new one with no luck. It just started doin this one day clear out of the blue and I have yet to figure this out. I dont know of anyone else havin this problem and I have done so much research tryin to find a tread like my problem with no luck. Maybe one of the wiseman could help out with this one.

My mods: stock 1G intake man, and TB. Evo 3 16G(ported w/ 34mm flapper) with 680cc inj. AEM fuelrail with FPR set at 43 psi. MSD DISII and Maft Translator 2.02. AFC2 and Palm. HKS cams 264in/272ex with adjustable cam gears. Full 3" exhaust with no cats. Aluminum Race Raditator. EGR block off. and a lot more!

Maybe someone out there will have an answer, thanks alot guys!

 

[Awsniper]

maybe your EGR blockoff is lose. On my EVO it was lose and it did this same thing. Them min i would touch the gas, rpm would shoot up to 2000-2500 and hold stedy. I would say try that. Once i tightened down those bolts, it idled fine. No CEL??

 

[peypey's ride]

Well, the EGR blockoff plate is on good n tight! With a gasket and sealent. Also, I dont even need to touch the gas and it will work its way up to idle high.

 

[RMeadows]

Have you been driving it around like that? What do your fuel trims look like? Before I took the time to fix my boost leaks and tune my car properly I would have an insanely high(steady) idle as well from the fuel being all out of wack. Just something to look at.

 

[ekanddsm]

Youve got a logger, what are you seeing at idle for isc? Long fuel trims? Short fuel Trim?
what is your O2 seeing, try lowering your fuel pressure to see what it does
Is you FIAV blocked off. Is it a 1g or 2g tb?

 

[peypey's ride]

Ok, update time, well the damn thing still wants to idle high!!! I double checked my ISC and the ohms are with in specs, 28 -33 ohms and its at 30 and 31. I set my TPS with the ohms meter and adjusted my throtlle cable to and its all good. I was reading one fo the other threads on here about fiav, and maybe blocken it off. I never had a problem before with it. In the faq, i was readin that it may also be a bad ecu, where the resistors that control the isc and fiav might burn out, so i pulled the ecu out and checked it, then I swapt my other ecu in to try that, same result!!! So now I have no clue!!! Any more ideas from you guys would help me out alot! thanks

Edit: I do have a 1g tb. My ltft is up to 17 when its idling high and about 7 when it idles normal, my stft is at 5 at high ilde and 2 at normal idle.