I'm too cheap to go out and buy a new intake plenum. Can I clean with warm soap water? I would dry it off completely before reinstalling. I'm going to clean the lower intake with steal wool or green scratch pad, not sure.

If you're going to go through all the trouble of RE&RE'ng the Upper Intake....Why not install something to help prevent the EGR problem too? Try something like this: http://www.pureperformancefever.com/...roducts_id=701

As on cleaning the lower intake & such....Try a 3M Scotch-brite pad. They come in varring degrees of grit. I suggest a fine or medium grit for the lower. Chemically clean the upper though, as scratching it in ANY way will cause it to leak! Just make sure the chemicval you use doesn't warp it too. FI/Sensor safe Intake cleaner & elbow grease is your safest bet though.

Aren't you Series I, you have a 94, right?

Are you just digging in to fix the gasket problems you have? Your car doesn't have the ludicrous series II intake, so you don't have much to worry about. Series I can have problems, but it'* rare.

Do NOT use an abrasive on the mating surfaces. Either where it mates to the upper intake manifold or the heads. Use chemical strippers for that only. I'd suggest a citrus degreaser or simple green to cosmetically clean the upper, and anything you want for the NON-mating surfaces of the lower. Scotch-brite, as Deathrat suggested would be a great choice.

pussled here what year 3800 came with plkastic intakes ...i had 2 L27`* both non-plastic....as is my series two custom ( lol ) intake

Yours were 92'*, right turtle? They had aluminum uppers with no EGR.

Not all of the 92'* were like that. Late production 92'* had the plastic upper and an EGR.

He said he had non plastic uppers, so I told him what he had. May family has 2 EGR'd 92 L27s.