High idle making me crazy

Chipofsc

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Still having this high idle problem after WOT. Done the procedure that Malcom posted several times. I know this is a problem with the single blade TB. I have been in contact with accufab and they suggested sending it back to them for calibration. It works great as long as you drive slow but once you hit WOT it sticks and idles around 1500 to 2000 rPMs. I put a large return spring on it just to see if it would help but it still hangs high. If you hit the throttle a couple of times it will come back down to about 1000. Hate to send it back but looks like I may have to.
 

cj428mach

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The problem is the throttlebody.

I've had 3 aftermarket throttlebodys 1 Accufab, 1 Billetflow, and my current GT500 Monster. The Accufab and GT500 are both capable of idling at 725-750 rpms with no tuning tricks or return springs, or any other crap. The Billetflow I had could idle at 950-975 at best with zero degress of timing and a return spring.

Send the TB to accufab if they'll fix it for you.
 

Chipofsc

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Sending it back this week. Just can't understannd how setting the stop screw to factory spec will help that much. Accufab said if you ever turn the stop screw you will have this problem.
 

MalcolmV8

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Sending it back this week. Just can't understannd how setting the stop screw to factory spec will help that much. Accufab said if you ever turn the stop screw you will have this problem.

It's not just a stop screw issue. Some of them are just poor quality and allow so much air to get sucked through at idle it causes high idle. The blade gets sucked open and held open by the engine vacuum. You can set the stop screw out to seat that slightly open position as its new "correct" idle position. Adjust TPS sensor accordingly, reset ECU and let it learn that as idle. Possibly have to pull timing from tune and adjust idle air integrator in tune as well to compensate. Now this new so called "stuck partially open" position will idle correctly and fix the issue. However they should just repair your TB and not have you go through all of that.

I had horrible luck with the Whipple mono blades leaking so much air. Whipple replaced my TB 3 times and while it got better it still sucked. They argued it was not the TB leaking air so I sealed it up with some children's play doh to prove it. Car went from a 1100 RPM idle or so to 700 RPMs. Yup their TB seals just great :bored:

IMAG1302_resized.jpg
 

Chipofsc

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Met a ford master mechanic this past week and he has helped me so much with the cobra. He found the gas smell coming from my evap system was not connected. The high idle problem he had me remove the tb clean it and the idle control valve. I noticed the light was even around the Blade when putting a light behind the blade. I loosened the screws and let the tb self center the blade then relighted the blade. Adjusted the blade so I had just a little light around the blade. Reinstalled the TB and set the TPS and .95. Made a couple of wot runs and it returned to 1000 rPMs. So much better. Not sure if it was the idle air control or the dirty TB but it's much better.
 

cj428mach

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Met a ford master mechanic this past week and he has helped me so much with the cobra. He found the gas smell coming from my evap system was not connected. The high idle problem he had me remove the tb clean it and the idle control valve. I noticed the light was even around the Blade when putting a light behind the blade. I loosened the screws and let the tb self center the blade then relighted the blade. Adjusted the blade so I had just a little light around the blade. Reinstalled the TB and set the TPS and .95. Made a couple of wot runs and it returned to 1000 rPMs. So much better. Not sure if it was the idle air control or the dirty TB but it's much better.

I don't know if I'd be happy with a 1000rpm idle.
 

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