Stuff like this is real hard to diagnose over a computer. You probably have difference between your commanded throttle position and actual throttle position. Try recalibrating the throttle. You'll have to search for that as I don't remember the exact steps to do it. If that doesn't help, than you're probably ready for a new TB. "Make every repair an upgrade"... get a ported TB!

 

Yep, I saw that as a possible solution. So I did try that a number of times. What was neat was initially after I cleaned the TB, I re calibrated the pedal, the throttle response was much better. Unfortunately it didn't cure the problem.

So who do I talk to about a ported TB?