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Discussion Starter · #1 ·
Just did the $0 thunder throttle mod. Throttle response is definitely improved, but now my engine seems to want to idle very high between shifts. When I come to a full stop, it settles down to a normal idle, but slowly. Is this normal behavior for this mod until the ecu learns what's up?
 

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What idle rpm did you get it set to with the IAC disconnected?
 

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Discussion Starter · #3 ·
Sorry, but that question went right over my head... It idles around 2500 between shifts and then falls back to normal over the course of several seconds after stopping.
 

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Discussion Starter · #5 ·
Well, my process was a messed up. I was not able to unset the set screw. I pulled out almost all of the visible epoxy, before breaking first a torx bit, and second the screw. I don't have any worries about finding a replacement, but first I gotta get the original outta there.

Think an easyout might work?
 

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Discussion Starter · #6 ·
Well, the ECU seems to be taking the new airflow in stride. My between-shift idles have calmed down considerably, and I can watch it while it idles searching for a sweet spot. A guy at work with a Mustang told me that generally, if the car figures it out within five days of the mod, you're okay; that's how much of a "memory" our ECUs seem to have about variable conditions. Any thoughts?
 

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It's tough to get the throttle plate set right if you don't have an adjustable stop screw.

Can't center it well without backing the screw off, and base idle speed adj. afterwards is tough as well.

Tom's suggestion might "save it" for now at least.
 

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Discussion Starter · #9 ·
Tom and I must think alike; when I put it in, and killed the stop screw, I did exactly that in order to best follow the official DIY directions. I still don't think I got it right though. The high idle has half-corrected itself, but if it wants to idle at 1.7k, and I put it in gear where the speed holds it at 1.5k, the car will actually accelerate slowly to 1.7k without my foot on the pedal.

I'm pretty sure my throttle plate is way outta whack now. Anyone have a guess as to the size/thread pitch of the stop screw? I want to try to remove and replace it, at this point.
 

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Moot question until you get the old one out and the example you use to match to new one. If threads damage upon removal you will need new TB anyway.

Bending throttle tab is butchery there, you have to be able to adjust to within a very few thousandths there. Doing that by bending IS possible but most will fail due to lack of patience getting it just right, why the screw is messed up to begin with. Epoxy removal requires great finesse when done on very small pieces.
 

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Discussion Starter · #11 ·
Noted.

At this point, the $60 replacement I found at a local scrapyard is looking pretty tempting. Maybe I'll put it in so the car drives normally while I try and fix the one I screwed up... or maybe I'll just grit my teeth and buy the CFM throttle body that I was inevitably going to purchase someday anyway. x_x
 

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Might be the best idea.

Unfortunately, if you don't have luck getting the block off removed enough to get the idle stop screw turning for adjustment that's the point to stop in attempting this modification. It just can't be done satisfactorily without use & adjustability of that screw.
 

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It is a pain getting that stuff out of there and getting the screw loose without stripping it! I bought a $20 tb off ebay or in the parts area to do mine. That way if you mess it up you have a replacement or second chance.
 
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