Can You Help Me With Some Idle Problems? Options

[JohnnyWadd]

Hey, guys. Some of you might remember me. I'm the guy that was going to grad school in San Diego that got his 1991 Talon stolen TWICE in six weeks. Well, I know I've been off of the map for a while. Sorry about that. Ever since I graduated, I've been in and out of the country, and ever since I went back to finish my studies, the Talon has been in storage. So, even though there are still a few problems, I've yet to start working on them. Well, that is, until now.

So, I pulled the car out. She hadn't been started in well over a year. Didn't matter, though. She started up with only a minimum of effort. However, I'm having idle problems. I was having this problem before I left, just never got around to fixing her. The biggest thing is that she's idling way too high. Somewhere around 2500 rpm all the time. She's supposed to idle a bit higher on start-up cuz of the cold idle switch. But, it's supposed to drop to around 800 rpm or so. She won't do that. Just stays around 2500 rpm. You guys got any ideas as to what to check on this?

Well, most of the time she stays at 2500. Sometimes, she'll go into a bit of an idle surge where it'll jump at a regular interval between about 1200 rpm and 2500 rpm. Weird!!

First off, let me tell you about the throttle body. The BISS is bottomed out. Can't screw it in anymore. Plus, the sensor that stops the throttle from falling all the way back (can't remember the name of it off the top of my head - has a single wire connector to it and screws sideways into the throttle body) is bottomed out, too. So, it's not a mechanical thing. Gotta be electrical, right?

Let me give you a little more background. Ever since I got the car back and resurrected her, I've had a few problems. I'm having turbo issues. My mechanic is convinced that the turbo is shot. It wasn't when they took it, but I guess that doesn't mean much. They raped everything else, so who knows what they did to the turbo. Also, I've got a constant hot that drains the battery overnight. So, gotta disconnect it or get a jump. My buddy's an electrician, and we're going to work on that this weekend. Not sure if my idle troubles are related to these other things, but I just wanted to give you an idea what we were looking at.

Other than these problems, my Talon is doing okay. She's not where she was before they took her, by any stretch of the imagination. But, she's doing good, all things considered. If you can give me some ideas as to what to check, I'd appreciate it.

Thanks for your time.
Jon

[JohnnyWadd]

Okay, thanks for all of the suggestions. I'll check on these ASAP.

Almost forgot to tell you. I did start a forum for this problem one time before. Forgot all about that since it's been so long since I put the car in storage. So, I didn't need to start a new one, but it's nice to get some fresh ideas.

One thing that I remember from before was that I started to lean towards the ISC being the problem. Not the motor itself, but for some reason, I don't think it's getting any voltage. Someone told me to test the plug. Can anyone give me any instructions on how to do this? It was also suggested to me that the part of the ECU that controls the ISC might be causing the problem and that the ECU might need to be replaced. Can this be tested with a test light or volt-meter? I'd hate to replace the ECU, then have that not be the problem.

As far as the ECU goes, it wouldn't surprise me at all if this turned out to be the problem. I replaced the ECU a while back, but that doesn't mean that the one that's in the car is the one I bought. Like I said, these guys did some weird stuff to my car while they had it. It wouldn't surprise me if the ECU in it now is the one that they had in their car (I'm convinced that whoever stole mine was after parts for their own). So, if you guys can let me know how to test this, I'll be forever grateful.

Once again, I'm sure it's not the BISS. I said that in my post that the BISS was bottomed out. And, I checked for boost leaks before putting it in storage. That's not the problem, either.

As for the Turbo, what we ultimately did was to cap the outlet, then put a pressure guage on that little vacuum outlet on the big outlet pipe. You know what I'm talking about? The black pipe that comes out of the turbo and hooks to the hose that runs to the intercooler. Anyway, when we'd rev up the engine, the pressure guage wouldn't go about 2 pounds. That's why he thought the turbo was shot.

Once again, it wouldn't surprise me if the turbo that's in it isn't mine. I can't say enough about the BS these guys did to the car. NOTHING would surprise me at this point. I just wish that I could work out these last few problems.

Thanks again for all of your help. I'll look into it soon.
Jon