Idle way high-need help ASAP

[Chris6050]

I just put on a 65 mm throttle body and EGR spacer. When I start the car, it idles really high, like around 1200-1300. I tried to drive it, but the throttle like sticks. Like when I shift say at 2000, it stays there and doesn't come down for a little bit. I bought the TB used and it didn't come with a TPS sensor, do I need to get a new one or does the stock one work? Need help ASAP b/c this is my daily driver and need to get to school tomorrow. Thanks.

-Chris

 

[Highbredcloud]

You can re-use your stock TPS...just make sure your voltage is between .95 through .99 Also what you can check is if the idle screw is in the middle of the TB where it should be...sometimes that could get wacked out of shape and cause high idle problems...

 

[Chris6050]

Ok thanks I'll check the voltage. I think I got the idle fixed, but the throttle just seems to stick a little bit. There was a spacer on the idle bypass valve (that cylinder looking thing, i think thats what it's called), I took that off and the idle is now back at normal.

 

[Chris6050]

Also, how do I adjust the voltage on the TPS if it is out of wack?

 

[DMAN302]

Check to make sure the butterfly is seating back properly, just figured out mine wasn't and the idle was very high and did hang when shifting..run the car pull off the inlet line and push on the Butterfly if idle fall then it's sticking.

 

[Chris6050]

Ok I'll try that. When I started it up this morning, the idle hung at like 1200 for a few seconds then when to normal. It definately sticks while driving normally. On the plus side, the idle sounds more chunky when it idles right. It doesn't surge or anything when its doing it right, just sounds lumpier. Someone at school thought I put my Trick Flow cam in there. I also will check my TPS voltage. How do I adjust it if it's not between .95-.99? Thanks.

-Chris

 

[Chris6050]

I tried pushing on the butterfly, but it didn't help anything. This is driving me nuts. The idle seems better, its the sticking throttle that gets on my nerves. The gas pedal also seems tougher to push in? Anyone know how to change the TPS voltage if need be when I check it? Thanks.

 

[NYC LSC]

Disconnect the IAC and turn in the stop screw to raise the idle to where you want it. If you've got no more surging idle problems, it's most likely your IAC.

I just went through the same stuff with my car a few weeks ago (throttle sticking betwen shifts and the idle problems). I've been running the car with the IAC disconnected since and it hasn't given me a problem. Cold starting is a little bit of a pain now, because you need to keep giving it gas. Once it warms up, it's fine.

 

[RacinChris]

Disconnect the IAC and turn in the stop screw to raise the idle to where you want it. If you've got no more surging idle problems, it's most likely your IAC.

I just went through the same stuff with my car a few weeks ago (throttle sticking betwen shifts and the idle problems). I've been running the car with the IAC disconnected since and it hasn't given me a problem. Cold starting is a little bit of a pain now, because you need to keep giving it gas. Once it warms up, it's fine.

Guys, I have the same exact problem. Kinda frustrating, so I'm running with the IAC disconnected for now, too. Had a friend look at it and he said it looked pretty new, recently bought (I've only had the car 2 months). With the IAC connected, the throttle does the sticking thing, and it idles too high. I turned the throttle screw down and got it to idle around 800 RPMs when it starts, but after running for a while and driving around, it settles in to about 1000 RPMs. I figured I might as well drive it with the IAC disconnected because it acts more normal. Cold starting for me is the same way, gotta give it some gas. After it warms up, it idles smoothly, doesn't stall, it's great. I just wish I could figure out how to make it run with the IAC connected without experiencing the high idle and the sticky throttle. If you guys figure it out or hear anything, let me know!

 

[RacinChris]

ttt

 

[Chris6050]

I switched IAC from the one that came with the 65 TB to the stock one and that fixed the idle problems and sticking throttle while driving. However, when I first start up the car after sitting for a little bit, the gas pedal is hard to push in for the first time. It feels like I have to break it loose, b/c once I push it, it becomes like normal again. When it sits over night, the next morning when starting it up, I really have to push hard down on the pedal "to break it loose" and then its fine again. Not really sure why it does that.

 

[RacinChris]

I switched IAC from the one that came with the 65 TB to the stock one and that fixed the idle problems and sticking throttle while driving. However, when I first start up the car after sitting for a little bit, the gas pedal is hard to push in for the first time. It feels like I have to break it loose, b/c once I push it, it becomes like normal again. When it sits over night, the next morning when starting it up, I really have to push hard down on the pedal "to break it loose" and then its fine again. Not really sure why it does that.

Hmmm, that's interesting. I still have the stock throttle body, however, like I mentioned, the IAC looks practically brand new. Maybe I can borrow the IAC from a friend's Mustang to see if it fixes the problem. Who knows, maybe the original IAC went bad, and the previous owner of my car went to a junkyard and bought a new looking IAC that just so happened to be the wrong IAC for a stock throttle body. That could possibly explain it, right?

Curious... what is the "butterfly" that DMAN302 speaks of? Do you have a picture or know of one?

Here are some pics of my IAC that I posted in a separate thread. You can see how new it looks, compared to everything else:

 

[Chris6050]

Yeah might as well try borrowing a friend's IAC and seeing if that helps anything. Couldn't hurt right?

By butterfly I think they mean the blade inside the throttle body that opens and closes when the throttle is applied. Thats what I think is sticking and causing my problem with the pedal being hard to push in....

 

[RacinChris]

Yeah might as well try borrowing a friend's IAC and seeing if that helps anything. Couldn't hurt right?

By butterfly I think they mean the blade inside the throttle body that opens and closes when the throttle is applied. Thats what I think is sticking and causing my problem with the pedal being hard to push in....

Yeah, I think I'll try that when I get a chance.

With the butterfly sticking... your pedal is only hard to push in the first time, right? Then it's fine? No more sticking throttle or RPMs hanging after shifts?

 

[Grn92LX]

I switched IAC from the one that came with the 65 TB to the stock one and that fixed the idle problems and sticking throttle while driving. However, when I first start up the car after sitting for a little bit, the gas pedal is hard to push in for the first time. It feels like I have to break it loose, b/c once I push it, it becomes like normal again. When it sits over night, the next morning when starting it up, I really have to push hard down on the pedal "to break it loose" and then its fine again. Not really sure why it does that.

Simple. It's because the throttle stop screw was backed out too far. Screw it back in more with the IAC unhooked and you should be good to go. Been there/done that already

 

[RacinChris]

Simple. It's because the throttle stop screw was backed out too far. Screw it back in more with the IAC unhooked and you should be good to go. Been there/done that already

Does that explain the sticking throttle problem? I've tried pretty much everything, and if I put the throttle screw closer, it'll idle at like 1500 RPMs with the IAC connected. I run it with the IAC unhooked, but I would like to be able to run with it connected, like it's supposed to.

 

[Grn92LX]

No, that sounds like a bad IAC or a vac leak.

 

[RacinChris]

No, that sounds like a bad IAC or a vac leak.

Okay guys, I took the IAC from my friend's 1991 Mercury Grand Marquis with the 5.0 and put it on my car, then reconnected it, but it didn't fix the problem. Same exact thing happened, with the high idle (between 1500 RPMs and 2000 RPMs) and the sticking throttle. The sticking throttle is the main concern really because I can turn the idle screw and set the idle to as low as 800 RPMs, but it would eventually level out at 1000 RPMs after warming up. It should be able to idle lower than that with the IAC connected, and the throttle should not be sticking. The throttle does not stick at all with the IAC disconnected.

What about a vac leak?

I've attached 4 pictures of the area near the throttle body... I'm not sure if everything is as it's supposed to be, like the throttle looks a little lobsided maybe ? Could you guys take a look at them and tell me what you think?

 

[Chris6050]

Grn92LX, good advice, that fixed my problem. Thanks

-Chris