Welcome to the SR20 Community Forum - The Dash.
SR20 forum logo

Thread: 5k idle completely stumped

+ Reply To Thread
Posts: 11-20 of 25
2008-03-24 21:15:33
there is backressure forcing the tubo to spin theother way thats what caue comressor surge

i have check and clean the throttle body its 100% closed
the tps is at .44v closed and almost 4v wot
i have cleaned and rebuilt the aac valve 3different times with no help
2008-03-24 23:52:33
Hmm that really is puzzling then. Probably something that when you figure it out you're going to have to smack yourself in the head for not seeing it sooner. I've done that a fair share of times

Try pinching off the air regulator hose and normally it should die then. It almost seems possible that if it were wide open you could have an idle like that, but I don't know. I know my IACV is a POS and I am 90% sure my air reg is jammed open. Right now I have a clamp on the hose to keep a low smooth idle but when it isn't on there, it surges to like 2k rpm. And on a cold start it used to be up closer to 3k. But 5k seems like too much to me for it to just be a stuck regulator.

So basically you are boosting but not supplying enough energy out of the exhaust to maintain the boost level? Now I'm doubly confused because I had heard you can't just boost without engine load. And if you were surging shouldn't you read a positive pressure on your gage, not negative? Or at least it should be changing and not constant.

If you suspect the manifold gasket is bad you could direct a small amount of starter fluid around it and see if your engine speed varies.
2008-03-25 00:09:11
You said you had a MAPS I don't know enough about them but that is my next guess. Maybe check some message board that has MAPS in there car from the factory and start trouble shooting there. You can pretty much rule out oe idle stuff it's not going to do that 5k revs unless some wires are crazy mixed up.

Also if you are getting back surge then you BOV wouldn't be working you might want to check that. Good luck the whole thing seems pretty weird
2008-03-25 00:14:57
Originally Posted by TeKKiE
TPS, maybe? If you're not reading ANY volts, it's GOT to be the TPS malfunctioning. You should read .46v with key in acc position, and about 1v at idle. If you read nothing, you need to replace it, or at least test to determine if it's your ECU that's causing the problem.

I didn't know TPS voltage changes by starting the car.
2008-03-25 00:19:42
well i am getting negative vacuum readings on my gauge at 5k -20in hg other than the high idle, the engine runs like normal i get positive boost pressures and it holds great, ive checked the map volts andthey are to par along with the tps volts. those 2 would effectthe engine load
2008-03-25 00:25:35
What engine management are you running to have a map sensor?
2008-03-25 00:32:01
aem ems
2008-03-25 00:49:12
Has it always had this 5k idle since the ems install or did it just appear? Try running the car without the idle valve plugged in, give it a little throttle.
2008-03-25 00:58:14
the idle valve is unplugged, and it still idles like that.

this just started and came outof nowhere, it used to idle at 1500rpm which is still highbut it has cams so its n out of the usual
2008-03-25 02:31:41
Originally Posted by Setzer
I didn't know TPS voltage changes by starting the car.

Oops! I was thinking MAF when I was typing that. :o You're right, TPS should be steady at .46v regardless of whether in acc position, or run position. Should only fluctuate when you depress the throttle in the car, or pull the throttle cable.
+ Reply To Thread
  • [Type to search users.]
  • Quick Reply
    Thread Information
    There are currently ? users browsing this thread. (? members & ? guests)

    Back to top