My car idles at 3k+. It's really annoying. I've replaced the ISC and TPS many times. I am waiting to change the LIM gasket because I'm lazy and I don't have time for it. I just want to try the easy stuff first. I have also have the AAS completly closed and all idle screws completly out.

My question to you fellows is....Can the ECU cause high idle?
Is there a way to check to see if the LIM gasket is bad?

 

have you taken the elbow off and see what's going on?

the ECU can only idle that high if the AWS is stuck wide open. nothing else can get that must air past the TB.

 

Yes, I have taken the elbow off numerous times. The throttle plates are fully closed. The AWS is disabled blocked off.

Now, if I have the car running, and then I pull the ISC wire out, nothing happens. This is probably related somehow.

Any suggestions?

 

the ISC can't idle the car up that high...

PCV capped or leaking?

take the throttle cable off and idle, just to eliminate the possibility

 

It's not the throttle cable for sure. I'll have to take a look at the PCV.

 

only other time I've seen a random idle that high is when the linkage was stuck...but you say, you removed the elbow...

well, earlier this week a guy had a towel stucked into the primary port of his TB and had a high idle...but again, you've checked.

what happened when this started?

 

Well, I had a hunting idle for awhile. You know, when the idle bounces from 800 to 1500 rpm So, I decided to dive into that problem by pulling everything from the UIM to the elbow off the car. When I put everything back together, everything better, just not perfect. So, I decided to pull everything apart yet again to fine tune it. Once, I put everything back together, then the high idle problem started.

How hard are u supposed to blow into the pcv. If i remember correctly, if blew hard enough, just a little bit of air came through when it probably shouldn't have, and no air came through from the other direction.

 

don't know...1995's didn't have one. Mine has been capped on the filler neck and UIM from day 1.

there is an idle screw under the elbow...on the TB. You can stick a small flat head screw driver in it. It adjusts how much air the ISC can bypass. Maybe tighten it all the way to see if you can lower the idle.

Does seem strange unplugging the ISC does nothing...do you have a leak there?

 

not to be a dik but the idle screw does not adjust how much air the isc can flow but how much baseline air(closed isc) the car sees. it souds like a vac leak

 

I'm going to cap that when I get time. Just to see if that is the problem.

Already tried that. It doesn't close any further. If i turn it the other way, it moves from 3.5k to 4k and so on.

Tell me about it. I will try to tighten it again. I think I put some gasket sealer in that location. I'm not looking at my car right now, and it's been awhile since I've driven it. I got frustrated with diagnostics from this problem about 2 months ago. I let the car sit around. (Well, I started the car just to keep fluids moving on thanksgiving, drove it with a high idle, then the car quit on me. <--- I think it is a bad alternator because I had to jump the car to get it running and when it died, I had no power for emergency lights. It was a fun push home....)

Is there a rotary guru in the cincinnati area that wouldn't mind coming out on a saturday afternoon..... I would do the same for anyone else.....

 

I don't like the sound of that.....if it's another vacuum leak I SWEAR I'M GONNA KILL SOMEBODY! I guess I'll have to check every line from the LIM on back.

Oh, I cut the heads of the rats nest if that makes a difference. I'm already running a tuned PFC. That's why I do not want to reset the ECU because then I would have to get my car re-tuned

 

Oh, I cut the heads of the rats nest if that makes a difference

what does that mean??

 

I went to a full non-sequential turbo set up. Those solenoids that used to attach to the the rats nest. I cut those things off. Should I not have?

 

fine assuming you capped all the lines. everything after the throttle plates needs to be capped or routed to the app spot. a can of brake clean will help see if it is a vac leak. 3k idle you should be able to hear it

 

Brake clean. I heard that starter fluid is good to use. Anyone had any experience with this. I don't want to keep 3 fire extinguishers and a hose on hand.

Once it stops being 10 F outside, I will take a look again at the problem.

 

that's not being a dick, that is correcting misinformation...which is what this forum needs more of.

Question though. why does the TB have two baselines then? The screw on the front side, cracks the primary butterfly...which is a constant air source.

Using my Haltech, I've got pretty good control of the ISC...and I use the bottom screw to aid tuning the ISC. That's why I always figured is had "something" to do with the ISC. I need to study my TB more...easy now since its off the car.

 

High idle has been solved. It wasn't the TPS nor the ISC. It wasn't even the AAS screw or the other idle adjustment screw. It was the wax rod assembly keeping the bottom throttle plate open. After countless hours and money spent, it was something stupid like that. Oh well, at the car runs well.

 

Hey i am having the same problem, how did you fix it?

My idle is around 1400-1500rpm and after a short drive, maybe 10 minutes, if i try to go in 1st to move the car up a bit, then clutch back in, the rpms stay up.

Example, i rev to 2k to move the car up, then clutch in, the rpm's stay at 2k for like 5 seconds, then slowly come back down to 1500 which is high already.

Do you think the wax rod is the problem here too?

 

That sounds like the wax rod assembly. It may be sticking. My stuck so bad that it kept the bottom throttle plate open, so my idle was at 3k. The wax rod assembly is supposed to be used during start up. When you start your car, the idle jumps to like 2k and then slowly works it's way down to 800 rpm.

I think your wax rod is sticking, causing you to have a steady rpm for 5 secs. before decending.

I don't have a picture of the location of the wax rod, but if you search, you can find it. You may have to get it unstuck by pushing it with a pencil, finger, metal rod, etc....or spray some compound like carb cleaner or WD-40 on it to keep it lubricated and working right.

This was the cause of my high idle.
https://www.rx7club.com/showthread.p...ight=high+idle

 

Yeah i know where it is, im gonna try what you said. Thanks alot for the advice.