Throttle Body Question
Thread Starter
Pro
Joined: Mar 1999
Posts: 560
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From: Fair Oaks CA
Throttle Body Question
I have the stock TB for a 1989 L98. Yesterday, I removed the TB cover plate and found some brownish liquid in there that has me puzzled. The cover plate has a plug molded into the rear part of the plate, the plug fits into a hole of some kind in the TB, and that hole is where the liquid is. It kind of looks like oil, but I have no idea why there would be oil in the TB. So before I do anything more, I'd like to find out what that liquid is and whether I should clean it out or not. Any comments?
Thanks in advance,
-WL
Thanks in advance,
-WL
Team Owner
Joined: Apr 2001
Posts: 22,267
Likes: 3
From: Dallas TX
Re: Throttle Body Question (White Lightning)
It probably is oil. Have you checked the small tube that runs from the rear passenger valve cover to the TB? Is there oil in that tube? If so, you have blow back from your valve area that is pushing oil into your TB. This is a VERY common problem with LT1's. I have the same problem, and so does nearly every other LT1 I know of. There is supposed to be vacuum on that tube and not oil coming out, leaking into the TB, and then into the intake. The way to fix it would be to put a breather filter inline with that tube. Putting a breather on both valve covers would be the best, but not something everyone would want to do. I'm getting ready to put them on both of mine.
