1999 Lesabre UIM/LIM? Problem

[brian_k24]

My moms car has about 77000 miles on it and there is coolant in the oil. My brother has removed the UIM and LIM and the gaskets and plenum look good. He inspected the plenum and went to a parts store and compared and was advised as to where they fail and everything looks good. Inspected the gaskets and neither the plastic frame or rubber seals show any signs of failure. He said they look just like the new ones.

He is now looking at pulling the heads but before he does that is there some other place to inspect before pulling the heads? From everything I have found head gaskets failures are not very common and would like any advise we can get.

Thanks
Brian

[HotZ28]

Did anyone look at the UIM behind the throttle body? Typical failure examples shown below:

[Robdaparamedic]

There is a common problem with these engines. They (NaPa) actually sell a kit to repair it. It is from the EGR port that comes out of lower intake manifold and vents into the UIM by the throttle body. The tube deteriorates and the coolant leaks into the lower manifold and mixes with oil. I did the job in about 3 hours, in my driveway. There was a guy on here that had a step by step diagram of the whole job. The kit I bought had the new tube and a whole new upper plenum with all the gaskets included. You have to remove the throttle body, fuel cage with fuel injectors, upper intake plenum, and vacume lines. Grab a pair of vise grips and rip the old tube out then tap the new one in with a little persuasion. You can leave the fuel cage in tact and just tie it up out of the way. Good Luck

Rob

[Hapynzap]

My 99 LeSabre had the UIM fail and hydrolock the engine. I fixed it and it runs great now.