Contour Enthusiasts Group Archives Forums General Troubleshooting New problem after TH fix

I did the TH fix and it worked well. I ended up with a hole of .199" with a #8 drill after starting at .160" and stepping up approximately .010" at a time. The tach now drops immediately to 750 with a millisecond pause at 1,000; I'm estimating the "millisecond". I am very happy with the TH fix and notice no loss in power at all.
Problem: I live on a steep hill and usually let my SVT go down in first or second gear without any throttle. My throttle sticks closed by the time I get to the bottom requiring an extra tap on the accellerator to free it. This now happens almost everytime I use engine compression to slow down for an extended period, ie., 10/20 seconds. Naturally this "sticking" didn't happen before the TH fix because my engine would rev up as high as 3,000, then drop off and rev again.
Any advice?
John
98 SVT

You're just gonna have to go with a bigger hole. PPL at higher altitudes, like myself, are gonna be prone to this irk. Just make it slightly bigger. It may not drop as quickly but it should drop quicker than it does stock.

HTH
John

Today, I took the rubber bellows duct off to clean the throttle body with throttle body cleaner. HAH! There is a factory sticker directly under the hose on the tb so you can't possibly miss it. The sticker says, explicitly, do NOT clean the throttle body because of the coating. Duh?
So, I increased the hole size in my TH fix plug to .218" from .199"
I still have the throttle sticking after using engine compression to slow down. It only takes a slight nudge to free it but it is still annoying. It definitely feels mechanical, the same as a carb feels when the throttle plate sticks due to the stop being backed off. Any more ideas?

Clean the throttle body and ignore the sticker. It is a load of BS. There is supposed to be a teflon coating to prevent deposits on the TB. It doesn't work worth a s**t.

Yes, definitely clean the TB anyways, and while your in there, make sure that the throttle plate isn't binding in the throttle bore because it's closing too far. If it does bind (i.e. feels like it sticks until you crack it open), then adjust the base throttle plate set screw 'in' slightly more until the throttle plate can close, but not enough to bind in the bore. Comprende? Good. Then after doing that re-adjust your TPS sensor to have like .94-.98 Volts at base throttle setting (KOEO) to maximize response (but NEVER set it over 1.00 volt). The factory sometimes has these as low as .6 or so volts. But the point of checking it, is to make sure that when you adjusted the throttle plate more open (to elliminate binding), that you didn't bump up the TPS voltage to go past 1 volt (which switches the computer into 'off idle' strategy). Then you'll probably have to re-calaberate the orfice size of your hole on the TH fix plug