[dBlast]

Ah, the re-occurring sticky FC 65mm TB problem. I have this problem occasionally, especially when its cold and damp. It's a pain when it sticks but when its working right it is the best feeling TB on the market. I have had the stock TB, Jackson Racing TB, BBK TB and the FC TB on my car and the FC feels the best when it's working. I was trying out the various TBs when trying trying to diagnose my JRSC problem with a vacuum leak that I thought was from the TB gasket.

There are various theories to why this TB sticks. Here are some below. Because my problem is intermittent and only occurs when it is cold and damp, I think it is due to the fact that the butterfly made of brass (I think) and the housing made of aluminum react differently with temperature restricting the opening causing the butterfly to stick when fully closed. Tap the gas hard to release the sticking and it works beautifully. Let off on the gas and it sticks. With all that TB swapping and adjusting that I have done in the last few weeks, the FC seems to be working fine now. It could also be the following:

This is a quote from FF about the sticky TB:

Quote:" a week or two of driving I started to notice what felt like the gas pedal was sticking and was requiring me to "pop" the pedal. After that initial pop everything was smooth, but anytime there was no pressure and the pedal and the car was essentially at idle, that first press of the pedal had to be another pop to get by the stickiness. As it turns out, and after seeing some other people experiencing that sticky feeling, I decided to take a look around under the hood. What I found out was that the idle screw on the throttle body was completely "backed off" and not making contact with the "hammer" on the throttle body linkage. I could easily place a piece of paper between the two. Just moving the linkage by hand I could feel the stickiness in the linkage. I adjusted the idle screw out until it made contact with the linkage hammer(see picture) and then advanced it another 1/4 turn to push the linkage just enough to open the throttle a very tiny amount. After doing that, no more sticky pedal or throttle. "

There was also a link to a "myfordfocus" which explains it:

http://www.myfordfocus.com/how-to/65mm.htm