I pulled my tb off and it looked like this:

Looks half decent for its age:


This is where I am at after some disassebling and cleaning:

New gasket:

Polished up my throttle plate:

All cleaned up and repainted:

I softened the back side edges with a wire wheel and high speed drill, also filled in the coolant passage with JB weld.

FIX IT NOW!!!!!

Sorry to yell, but you have a UIM failure/LIM gasket failure. I suggest you get it repaired ASAP, if you value your engine.

http://www.bonnevilleclub.com/forum/...e=article&k=38

funny thing is, its not leaking anymore. That and my tb is still cool to the touch after running for a hour.
But you are right, I will have to do it sooner or later.

No way. That clean throttle plate is a MAJOR clue. It should be sooty and black. It'* clean. That means MOISTURE.

Tear that sucker apart ASAP. Watch your oil and coolant like a HAWK. That TB should NOT look like that after 5k miles.

Moving to 92-99. This isn't a Performance topic.

I did clean it last year but I understand what your saying Will, its almost like its getting steam cleaned. I did notice a little steam comming out of my exhaust and I was like I shouldn't be able to see that till winter. After plugging the coolant passage and a new TB gasket, I will still keep a close eye on it even though the leak appears to have stopped and no more "steam" comming through exhast after running for over an hour.
I may have fixed this problem but I know you guys are right about having to change my UIM ASAP. Will your opinion is almost god when it comes to bonnevilles. I will change UIM ASAP.

You have not fixed the problem until you replace the UIM and LIM gaskets.

Whether it leaks or not, you still have a problem. Invest the $200 before it costs you your motor.

I will do it in 2 weeks crossing fingers. I expect to bonus this month so I will have the cash. I did notice a little(very very little) extra snap in the throttle response. These 3800'* are ****** for air flow arn't they? It seems like it loves to be tweaked and smoothed over and there are plenty of places to smooth. LIM, TB and so on...

Bill and Bill aka William. We don't know from the pictures if the problem was a TB gasket or an UIM. The coolant in one pic looks a bit close to the TB and not even near the EGR stovepipe area.

Toasted had coolant leaking and was pretty sure his UIM had failed. We changed what was a perfectly good intake (I checked the bore with a pick and screwdriver, it looked and acted like a new intake) over a TB gasket.

TB gaskets are possible while being more unlikely, it is possible. If the steam has stopped coming out the tail pipe, my thoughts would be a bad TB gasket at this point.

Worth guessing?

Probably not. If it'* an OEM upper, certainly not. It needs to be changed regardless.

I agree it should be done. I didn't quite agree that it appeared that we shot first and diagnosed later.