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Discussion Starter · #1 ·
My BBK throttle intake is sticking. Feels like the blade is getting wedged in. Whatever it is it's physical. Occurs with the car off, so it isn't vacuum lock. Anyone else encounter this problem or know of it? It isn't a big deal, just a nuisance. Travel is nice and smooth after the first half an inch or so of pedal where it's sticking.
 

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You need to adjust the throttle stop screw--here is how...
 

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I can't adjust it any more and keep the idle under 1k... I've tinkered with the set screw quite a bit.
Some BBK throttle bodies are made with a very narrow bearing surface for the blade shaft, at the bellcrank side of the housing:



I have fixed (cleaned up and lubricated) a couple of them that got jammed up, on one I had to remove the blade and pull the shaft to trim the plastic spacer which seemed to have swollen up--or never fit correctly.

Pro Products, Trick Flow and others use a different design with a wider bearing:




Also, did you disconnect the battery for 5-7 minutes after making the adjustments?

And are you sure the IAC is working properly--here is how to test it:

  • With the engine warm and idling disconnect the IAC electrical connector, the engine rpm should drop significantly or even stall--if it doesn't the IAC is bad buy a new one;

  • You can check the IAC with a multi-meter, unplug the electrical connector and measure the resistance between the two terminals, it should be 6Ω to 13Ω--if it isn't the IAC is bad, buy a new one;

  • Next check the resistance between each terminal and the IAC body, in both cases it should be better than 10kΩ--if it is less thee IAC is bad, buy a new one;
  • Check the voltage between the red wire at the IAC (connector plugged in, key on engine off (KOEO) and ground (the IAC body will work), it should be 12.0V or more--if not you have a wiring problem.
 

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Discussion Starter · #5 ·
Battery was disconnected during install and I followed proper procedure for the re-learning process. IAC is functioning correctly. I replaced a defective unit recently and tested the new one after installing the new TB. Wasn't even dirty yet. I'll have to inspect the bearing and blade. I'll report back with any updates. Thanks!
 

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Had it happen to my brother on his 5.4 swapped mustang he has a 78mm bbk throttle intake what we ended up doing was bending it a bit to stop it from getting stuck on the hood. And it too would do it with the car off as well.
 
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