I've got a 52mm TPIS rebore TB. It has almost always been flakey on returning to idle. I've always blamed the way TPIS must make them because it has always had this problem.

Today I got out a small scotch brite and carb cleaner and went inside the bores. Sure enough there was a small ridge of carbon just inside the throttle plates. Cleaned it all up and felt that I was hasty in judging the quality of workmanship.

Well I was wrong. I took the car for a test drive and the fargin TB still hangs. WTF? It feels mucho smoother now, where it used to feel notchy, but it still hangs up.

While the engine is off and I'm under the hood it seems to always come back to the throttle stops when manually moving it. This started me thinking. Could the return spring be weak? That combined with the air being drawn in preventing the blades from snugging back down when I take my foot off the gas.

Any theories or answers?

 

https://www.thirdgen.org/techbb2/sho...hreadid=119568

Hes having the same problem as you are... read my explanation and youll get it!

 

Basically what I said. Only problem is this is a rebuilt/rebore from TPIS that has been to some degree like this from the get go.

Guess I'll have to talk with them and see what I can do.

Thanks

 

The throttle blades are sticking in the bores. Common problem.
Pull the throttle body and open the blades then spray just a little
bit of black paint in from each side. Wait for the paint to dry for
a few seconds then let the blades snap shut hard. Open them up
and look for where the blades cut into the paint in the bore.
Use a small file or sandpaper to smooth the blades in the proper
areas.

If you have a sharp contact area all the way around the bore,
smooth the blades all the way around or put on an extra return
spring like I did.