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View Full Version : Sticky throttle on a turbo car


TitaniumTT
04-26-2009, 09:33 PM
Not a question, just something REALLY interesting that I found out the other day.

So the car was running GREAT, throttle body not giving me ANY problems whatsoever, and this was after I totally disassembled it (including butterfly shafts and seals) to have it ceramic coated. The thing ran great for a few weeks and made pull after pull on the dyno with no problems at all. Then some fucktards overheated it. So I'm driving down to NC and I drop 2 gears to get ahead of a slower car (oh a hondu :suspect:), redline in 3rd and shift, the car over revs', odd, then I hit 4th and tap the brakes becuase, well I'm doing 90+ in a 55. The revs drop in 4th and then the car starts to accelerate on it's own..... a little frightening.

We pull over and I find that the secondaries are sticking. :confused: So I put them back in their place and we continue on our way. The problem gets more and more frequent as the w/e wears on until it finally starts happening EVERY SINGLE TIME I GET MORE THAN 3lbs of boost. What I found was........... interesting

The boost was pushing the aft secondary throttle shaft seal out of place and binding against the throttle stopper keeping the secondaries from closing. So with a little motivation from a flathead screwdiver I pushed it back into place. 1st gear pull - cool, second gear pull....... stuck again - now I'm seeing red.

So I get the car home and get it as hot as I can - ~185* :lol: clean the seal where it presses into the TB and smear a little loctite 262??? the red threadlocking stuff around the press seal and wedge it back into place. Let the car cool, and proceed to BEAT THE SHIT OUT OF HER for 2 hours..... the seal hasn't pinned the stopper yet.

Just thought I'd share if anyone is having sticking throttle issues.... one more bizzare thing to check.

vex
04-27-2009, 11:43 PM
You say this now, after I took mine completely apart, ported/polished it, let it sit for 2 months while I dick around with the car and then attempt to put it back together?

Actually, to be honest, I ended up using your website and pictures to help me remember how to put it all back together.

classicauto
04-28-2009, 08:30 AM
mine started sticking on the dragon too - but mine was just age. Dripped a little 2 stroke oil on a the springs and all is well.

Interesting though, its fun when the car tries to drive itself around! Not so fun coming into a corner though :lol:

TitaniumTT
04-30-2009, 07:33 PM
While it's certainly something I'm capable of and have successfully done several times before, I never like to, and do not recommend others to, disassemble a working throttlebody and then put it back together. No matter how good you are, the throttle body is never 100% of what it was before you tinkered with it in my experience.

I agree, it is a royal PITA as there are SO many little things that need to be just right for the TB to function properly, but I didn't want the TB to be the ONE thing that wasn't ceramic coated. Not to mention the choke plates came out and I welded the shaft openings shut before polishing the thing off. It was a pain, but I think with time and a little tinkering, slight bending, it'll be everything that it was. It practically is now. Every so often it gets a little hung up, like 1% on the TPS log, that can actually be slight voltage variations.

You say this now, after I took mine completely apart, ported/polished it, let it sit for 2 months while I dick around with the car and then attempt to put it back together?

Actually, to be honest, I ended up using your website and pictures to help me remember how to put it all back together.

Pics saved my ass when reassembling. I think I took about 50 pictures. Everytime a pice came off, I snapped a pic, then everything was layed out in the order it was removed, then a pic was taken

mine started sticking on the dragon too - but mine was just age. Dripped a little 2 stroke oil on a the springs and all is well.

Interesting though, its fun when the car tries to drive itself around! Not so fun coming into a corner though :lol:

Tell me about it Joe! It happened one time when I was trying to slow down to pay a toll. Sketchy, VERY sketchy to say the least.