Has anyone else had a throttle body leak issue on their fast 92mm throttle body? I just installed my FAST 92/92 and tested it for leaks, and this is what I saw, smoke comes out from the throttle body shaft. Is there anyway to fix this? If not I am going to send it back to fast for warranty on monday.

http://www.youtube.com/watch?v=kZjWyH_RqJI

 

well why is there smoke in your intake anyway? thats weird. it looks like its barreling out as soon as it moves from resting position. was the car running for long enough for the intake and TB to heat up? if they are brand new, it could be roasting out some extra assembly lube from inside the throttle body shaft and the contact surfaces. i would drive it for a while and see if it continues when its had plenty of time being hot

 

He is using an evaporative emissions tester - a "smoke machine". It can be used for detecting exhaust leaks and intake leaks as well.

some_punk: Why would you purchase a FAST throttle body with their extensive history of failure? Good luck on getting them to cover that under warranty. And while I've never checked my intake tract, stock or PTM 92mm throttle body, I can say that throttle shaft bushing leaks and IMRC shaft bushing leaks are VERY common when using this testing method. What size leak is that? If it's under .020" orifice I wouldn't worry about it.

 

I agree. All throttle shafts leak a little, if not when new, when they wear in and it's not a problem as the IAC adjusts for the extra air.

 

I am getting a new one from fast, but I have heard that the issues from the 90mm throttle body was fixed in the 92mm throttle body, and FAST said that this is the first issue they ever had of it leaking.

 

Not many people actually check their throttle bodies for vacuum leaks. And even if they did AND reported it to FAST, I doubt they would tell you or anyone else that it is a common problem.

 

Well I got a new throttle body from fast, and guess what. It still leaks from the same spot. Has anyone else put a smoke machine on their car to check?

 

That air coming in from the throttle shaft is unmetered air. It is going to be running lean. how can that not be an issue?

 

Again, it's probably normal.

AGAIN, how big is the leak? Factory PCM calibrations often have provisions for a small amount of unmetered air.

 

It's not an issue because your car has a computer running it and sensors to feed it info. A small unmetered air leak might cause a slight lean condition which the O2 sensors will pick up and the computer will then add a tiny bit of fuel thru the injectors to offset it.

 

In open loop it doesnt look at the O2 sensors, my first throttle body was leaking so much it was going into open open loop fault. MY second throttle body was still leaking but it was able to stay in closed loop so I decided to stick with it and tune it to accomodated it.