Re: Unusual fast idle condition
 

Yes that's what we did to mine as well. Marc said the return spring gets weaker and he adds a small one to help w the closing. Mine works fine now and frankly I like the additional resistance. There's a more direct proportional feel to the pedal.

Re: Unusual fast idle condition
 

What a small world. I too worked at Tek but then who didn't back then. One of my pensions is coming from Danaher the parent of Tek. I was in the Oscilloscopes, Logic Analyzers and later Printer group for a total of 19 before moving on. Bet we know some folks in common.

Re: Unusual fast idle condition
 

Most initial failure on the TB is the plates sticking to the sides and/or top. From the factory they come with a special grease at and around the plates (some stuff used on the IAC) . People tend to over clean these. Later on as the bushings wear there is too much sloop and sticking becomes more frequent. A good way to tell is "blip" the throttle. If it slows down you got it.
Yearly cleaning is required. (or 60mo depending on use) I use axle grease on the edges of the plates (including the small idle plate in the middle at the bottom).
My personal preference is not to use an extra spring. It stiffens the peddle too much for me.