High idle after TB swap

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McNasty
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High idle after TB swap

Post by McNasty » Thu Oct 02, 2014 4:30 pm

So I went the BBK route, hooked everything up, fitted my Neon TPS and throttle cam, used gasket sealant everywhere, blah, blah, blah. It seems that my IAC doesn't want to close enough to bring the resting idle below 1500 RPM. Coasting idle is ~3000 RPM. I know I'm not going to blow up the engine, but I don't like hard shifts and burnt clutches.

I don't know if this is just the pcm in a learning process, but the IAC is good. When I pull the plug, it snaps shut and the car chokes. Also, if anything, the BBK's inlet/outlet ports for the IAC are a bit smaller than those on the Neon TB. I'm getting pretty frustrated with my car sounding like a guy who's trying to pinch a mad loaf.
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occasional demons
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Post by occasional demons » Thu Oct 02, 2014 8:29 pm

Check your TPS voltage if you can. It might be too high, if it is you may need to make it adjustable, or possibly the TPS is not located correctly on the throttle shaft.

If it was a vacuum leak, the IAC would already be shut, in an attempt to slow the engine.

Did you use the V6 56mm BBK?
Bill
Olha Koba, a psychologist in Kyiv, said that “anger and hate in this situation is a normal reaction and important to validate.” But it is important to channel it into something useful, she said, such as making incendiary bombs out of empty bottles.
2000 Neon MTX swap with '02 R/T PCM
1999 neon coupe 2.4 swap
2021 Forester

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McNasty
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Post by McNasty » Thu Oct 02, 2014 8:50 pm

Yep. 56mm of polished glory. I'll try to test the TPS tomorrow.
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Post by McNasty » Tue Oct 07, 2014 12:02 am

You were right, Bill. The mounting holes on the BBK are about 15 degrees too far clockwise to allow the correct reading from the TPS. I basically went with your Mustang TB/Neon TPS fender washer solution.
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occasional demons
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Post by occasional demons » Tue Oct 07, 2014 7:15 pm

Dammit, that sucks. By eye, the holes appear to be a perfect match.

Well at least you got it solved, and have a little step up in performance.

Altho I must admit, for ~15º, I would be tempted to heat the driver end of the throttle shaft and tweak it a little. Of course you would have to take it apart to do that, and for the $$$$, it would be understandable if you were reluctant to do that.

Did the driver end actually fit without having to file it, like I did the 60/65mm TB?
Bill
Olha Koba, a psychologist in Kyiv, said that “anger and hate in this situation is a normal reaction and important to validate.” But it is important to channel it into something useful, she said, such as making incendiary bombs out of empty bottles.
2000 Neon MTX swap with '02 R/T PCM
1999 neon coupe 2.4 swap
2021 Forester

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McNasty
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Location: Denver, Colorado, USA

Post by McNasty » Tue Oct 07, 2014 8:36 pm

Nope. I still had to file it a bit. I'm about to post a write up in my progress log. Hopefully I can save others the :cussing: over this setup.
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occasional demons
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Post by occasional demons » Sat Oct 18, 2014 11:13 pm

viewtopic.php?t=36541

Click on "This lovely device".
Bill
Olha Koba, a psychologist in Kyiv, said that “anger and hate in this situation is a normal reaction and important to validate.” But it is important to channel it into something useful, she said, such as making incendiary bombs out of empty bottles.
2000 Neon MTX swap with '02 R/T PCM
1999 neon coupe 2.4 swap
2021 Forester

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McNasty
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Posts: 47
Joined: Mon Jun 02, 2014 2:05 am
Location: Denver, Colorado, USA

Post by McNasty » Sat Oct 18, 2014 11:18 pm

occasional demons wrote:viewtopic.php?t=36541

Click on "This lovely device".
:shock: There may be hope for your namesake yet!
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