I found a boost leak around at the TB shaft, and decided to replace the shaft seals. I went these replacement shaft seals from Mach v:

http://www.machv.com/throtbodseal.html

I pretty much followed these instructions step by step:

https://www.evolutionm.net/forums/sh...d.php?t=220264

I lubed up the shaft and seals with dielectric grease, put everything back together, and everything went smoothly.

Now when I drive, the throttle intermittently gets stuck open. For example, while driving, I'll let off the gas pedal and notice the car is still pulling (as if I had cruise control). Then I drop it in neutral (or push the clutch in) and the revs will stay at 2000-4000 rpms (once or twice they climbed 5000 rpms).

So then I tried scrubbbing the inner walls of the TB with throttle body cleaner and a toothbrush. I also tried to lubricate the throttle cable with a little lithium grease. In spite of all this, the sticking problem hasn't changed. This leads me to think that maybe the TB seals are too snug against the shaft. I did have to push pretty hard to get them in.

I'm debating on whether to remove them and go with the WORKs seals:

http://www.worksevo.com/store/produc...roducts_id=415

or keep the Mach V seals in and wait it out -maybe they'll wear down a little and the problem will go away.

Anyone else have this problem?

 

My WORKS seals have operated flawlessly.

Just FYI.

 

Ive got the Mach V seals. It was sticking pretty bad before I replaced them. Now it only sticks sometimes on lift off from WOT, but always when I let off at around 5k. I seem to remember reading here on the forums that the ECU will sometimes keep the throttle open to burn off the unused fuel. But dont woute me on that. I replaced my seals about 8 months ago, and it has stuck about a dozen times.

 

Here is a link to the thread about the ECU holding the throttle open.
https://www.evolutionm.net/forums/sh...cking+throttle

 

my guess is that the blade isnt centered well.

the works seals bite onto the tb shaft more than the machv's...

i suggest pulling the tb, getting a few feeler gauges, remove the .002" & .0015" blade & use these to center up the blade if you havent already...

 

Centering the TB blade is something that I didn't do. Maybe I'll try that first.
Thanks.

 

Good advice WOT.

 

Hi TonyG,

I haven't heard this from any other customers, but I suppose the seals could be the problem. If you do figure anything conclusive out, let us know.

--Dan
Mach V

 

WOT is the man. I owe him a beer.

I removed the TB tonight, and inspected it. I could reproduce the sticking by opening and closing it by hand. It certainly looked like the throttle plate was dragging against the wall of the TB and getting stuck open.

So I removed the throttle plate and re-centered it. I didn't use feeler gauges. Rather I just held it up to the light and looked for a uniform ring of light between the perimeter of the plate and the walls of the TB. This was good enough to solve the problem. The throttle plate opened and closed very crisp and cleanly.

I put everything back together and went out for a drive.

No sticking

Problem solved, thanks to WOT.

....and thanks to Dan at Mach V for his prompt reply and offer for support. The seals are fine. They don't stick, and they certainly fixed the boost leak at the TB.

 

Aby (WOT) knows his shizzle.