Throttle Boost Leak

[jstefano]

I just finished a boost leak test and found a boost leak at the throttle body shaft. The leak goes away as I move the throttle with my hand. I ordered the o-ring and not the shaft seals that I should have and had my mechanic take it apart and put back together. I asked if I should order the shaft seals before he put throttle body back together. He insisted that the shaft seals would not solve the leak and instructed me to buy a whole new throttle body assembly.

My questions are: Will new shaft seals solve this leak or do I need to buy a whole new throttle body assembly??
If I do need a new throttle body assembly, what are my options?
Any help would be appreciated as I have searched all forums and still cannot decide what to do next.

 

[Talesin]

They might, they might not. Your mechanic is there and has his hands on the part though, so I'd be inclined to lean toward his opinion. You can always get the shaft seals and give it a shot though.

If you do have to swap throttle bodies, may as well switch out for a 1G TB unit, and port/gasketmatch the intake manifold to the larger throttlebody. Minor performance gain, and you can find the part for a whole lot cheaper than Satan wants for a new OEM 2G unit.

 

[jstefano]

Thanks for the advice. Where do I buy a 1G throttle body? Do I buy it from the dealer or do I have to send in my old throttle body in exchange for a 1G throttle body somewhere. I am guessing that Satan is the dealer ? Does it cost more for a 2G than a 1G?

 

[Talesin]

A junkyard would be a valid place to pick up a 1G TB. Just make sure it's not damaged, and read up beforehand on what's needed to make the swap work.

Yes, the dealer is Satan, due to how much they overcharge for everything. I really should leave this to a 2G guy, for all I know your mechanic could just be full of it. Did you inspect the TB yourself? Did he have a reason why new shaft seals would not fix the problem?

 

[daren_p]

First off what makes your mechanic think that the shaft seals won't fix the leak? The symptoms of the leak you described are exactly the symptoms of leaking shaft seals. It is very common for these seals to leak & a simple replacement of the seals is the fix 99.9% of the time. I prefer the "blue" shaft seals as they should last alot longer then the orings but the orings should still seal it up.

Personally I think its only the shaft seals but if it turns out to be something else, do not go to the dealer for a new TB (your wallet will thank you). You can pick up a used or reconditioned 2g TB for pretty cheep or like was said you can swap out for a 1g version, which is a larger diameter but you have to port out your intake mani to match the new larger diameter TB & the vacuum hose connections are abit different. If you want a larger TB but don't want the hassle of swapping to a 1g, you can get a bored out reconditioned 2g TB from places such as www.throttlebodys.com that will be a direct bolt on (still have to port the intake mani to match)

 

[jstefano]

Thanks for all the info. I will go ahead and order some new shaft seals first before I replace the entire throttle body assembly. I will keep you posted how it works out.
My car is running fine otherwise aside from the idle surge that I am guessing is a result of this boost leak. Thanks again.