3100 headgasket or lower intake manifold gasket?

[DeliciousAntifreeze]

HELLO EVERYONE.

I am the proud husband of a 1996 Chevy Lumina (the car) 3100 series engine.

I have purveyed your board in some kind of strange stalker fashion where I never talk to you but read everything you do. I have found this thread which suggests that the headgasket may not be the problem but rather when things go screwy, the lower intake manifold gasket is the problem.

The symptoms are that the engine decided to become "loud" (it does not tick, but it roars) and used all the coolant. My wife quickly pointed this out to me and I managed to dump a ton of antifreeze into the engine before all hell broke loose. the temp gauge never wobbled, but the reservoir was almost empty when I got to it.

Point being: The antifreeze was gone but the normal mayo looking stuff that normally means the antifreeze went into the oil was NOT present. The antifreeze had all burned off, fouling all the spark plugs. The mystery is why the engine is using antifreeze but not fouling oil. I dumped some stop-leak stuff in there (BARRs makes a goody) to buy some time and decided I'd better Ask The Mob.

So, 100, what do you think? I have no loss of power, but the engine is loud. I have no antifreeze (the BARRs stopped the leak and the engine is holding pressure), but I also have six fouled sparkplugs. LIM gasket?

Thanks in advance.

[TazMan]

Did you check your engine oil too or just your radiator for that mayo looking stuff? If all that antifreeze went into your oil that could be why your engine got so loud. I can't really answer your question that well as I don't know as much as the other guys on this board, but I do know if you have any coolant in your oil it is VERY bad for the bearings to run the engine like that. The loud noise coming from the engine isn't a loud knocking is it? You should definitley check your oil if you haven't already done so, and make sure it doesn't look like there's antifreeze mixed with it, however I've been told that antifreeze in the oil can damage bearings way before it is actually visible.

[DeliciousAntifreeze]

I checked the dipstick and pulled the oil fill cap, I haven't actually flushed and filled the oil pan. The dipstick doesn't have foaming on it, the oil cap might have had a smidge but it wasn't anything noticeable. From what I can see peering into the valvecover, there is not a significant amount of mayo in the works.

It's not knocking so much as it ROARS. I thought my wife had knocked off the exhaust pipe in the snow when she mentioned it to me (it's only recently become warm in PA), but it is NOT ticking.

I may just dump the car on the used car lot and let them deal with it if no-one any any solid ideas, but I appreciate your post.

[bszopi]

Seeing as it seems the engine is just loud (the coolant might not have anything to do with the issue), I would check anything that has to do with the exhaust system. Could have broken something (I've heard of cracked exhaust manifolds, although not very common), EGR tube could have busted off, etc...