[cadgear]

The lower intake gasket failure is a common (if not guarenteed) problem on the later 3100 V6 engines. What happens is the gasket breaks down around the coolant passages in the lower intake manifold, which will let coolant out one of three ways: a) Outside of the engine, not always visible on the ground; b) Into the crankcase, obvious signs like oil sludging would be present; c) into the intake path, where it gets burned in the cylinders. The last might not *always* produce white smoke, especially if it is a slow leak over a long time. However, as in my case, it would pool in a crevice in the block and evaporate without a trace but with a strong smell of coolant.

I hear alldata.com has things like that, but I've never checked it out; I have access to shop manuals and GM Service Information so I never really bothered. Though the first thing I do when I get a new/used car is go out and spend $15 on a Haynes (or chiltons) manual for the car. Great low-end approach at fixin' stuff. I took it a step further and bought a set of 99 shop manuals for my Lumina, just in case. Not a bad investment, though definitely not for everyone. I'll help out where I can; I had a headache of a time tracking down wiring when my dash guage was inop while the PCM read correctly.