sssmokin!!

[rockit-man]

Not in a good way either. White smoke. uggg. Only had the car a month or so. I have also found little puddles on the rear portion of the LIM, so I'll be ordering a APN kit very soon. I checked the date on my UIM, and it was manufactured in 01 and has the delphi sticker on it, so I know it has allready been done at least once. But now I have a question, how can I tell if I have the original engine, and what year it is? Is it possible that I have a 2001 engine with the original UIM? Also, I know this NEEDS to be done asap, but how long can I push it for? This is my only vehicle, and this comes at the worst possible time (of course) I am moving, and I have 4 new jobs starting up this week. Week end jobber?

[bill buttermore]

White smoke? If you are pumping enough coolant through your combustion chamber to create white smoke, you will have some coolant sneaking past the rings entering the crankcase, maybe a lot of coolant if the LIM gaskets have failed. Safest course is to drain the oil and coolant immediately. Pull the spark plugs. Change oil and filter using cheap, 5W-20 or 5W-30 oil. Leave the cooling system empty. Unbolt and disconnect the connector to the ICM. Spin the engine with the plugs out several times for several seconds at a time. Wait at least a minute between spinning it so you don't overheat the starter. That will flush any coolant away from your bearings, and prevent any (additional?) damage. Then, having protected the bearings, you can do what you need to do to repair it. If you drive it with an internal coolant leak, there is a very good chance you will damage or ruin the engine bearings.

Please read this: Techinfo UIM/LIM gasket failures

[rockit-man]

After reading the techinfo article, I believe that the LIM gasket is gone, but I haven't given up on my UIM yet. I am going to purchase the gaskets first, do the tear down and inspect the UIM, and if I need to, I will order the APN kit. Since the intake on there is a 2001, would it not allready have the reduced diameter pipe to help protect the plastic?

[bill buttermore]

Since the intake on there is a 2001, would it not allready have the reduced diameter pipe to help protect the plastic?

Only if the LIM was changed for a newer one, too. The stovepipe is driven into the aluminum LIM and is not part of the UIM. The reduced diameter stovepipe was an aftermarket invention of Ken Spragg. Ken rightly figured out how to solve the problem and sold a kit to modify your own UIM comprising a metal sleeve and a reduced diameter stovepipe. GM did not get on board until 1999, and they simply changed the stovepipe bore from 3/4" to 5/8" in the Lower Intake Manifold, and provided a straight piece of 5/8" stainless tube, instead of the 3/4" tube they used in the 95-98 models like yours. For years, GM dealers doing the work would change out the entire LIM just to provide that smaller stovepipe. If your LIM is stock, and unless someone found an aftermarket reduced diameter pipe for it, it will have the same old 3/4" pipe right up against the plastic bore of the UIM.

[rockit-man]

Ahh, I see. I think. If this is the case with my car, what is my best course of action? Does this mean that I should still purchase a UIM to get the reduced diameter stovepipe? I saw the repair kit, but for an extra $30 I can get a whole new intake plenumn, so why settle for just the repair kit. I see that the best gasket for the job is the aluminum one from the stealership, but is the felpro a decent alternative? I called in a price for the aluminum gasket and they were over $130 here. I tried the GM parts direct website and couldn't find them even with the part number. I'm not trying to cheap out here, I just don't have alot of money to spend on this right now due to a move, and I need to spend wisely.

[bill buttermore]

Best value and best repair quality is the APN kit for $115 delivered to your door. Check out intense racing.com for the L36 aluminum LIM gaskets, they sell 'em for $59. You will pay $45 for plastic. Not much of a difference for the best possible repair. If you have Dex, get rid of it.

[willwren]

I've seen newer GM UIM's fail. Get the APN.