There is a major recall and lawsuit pending at GM for the improper formulation of there engine coolants. The chemicals seem to cause intake manifolds (plastic) to melt and/or gaskets to dissolve or break. You should try getting in touch with a GM representative. Arm yourself with a copy of the GM lawsuit materials available on the web, and hope for the best. The PCV valve has nothing to do with this issue. It is a design flaw and a compatibility problem. Almost all GM V6's are affected, and many GM 4cylinders. By rights, they should have informed you about this problem through the mail. If I were you, I would register a major complaint at the dealer and ask them why they didn't tell you about this issue. When the gasket begins to leak, coolant is drawn into the combustion chamber instead of staying in the cooling system where it belongs. The coolant level steadily drops and you lose power and MPG's. When the level drops enough, the cooling fan won't go on and WHAM!!!, you're over heating. Some cars require the installation of a brand new INTAKE MANIFOLD!!!! GM is not admitting fault on this matter. Do yourself a BIG favor! Insist on using a Fel-Pro gasket, have your entire cooling system flushed out, then have Mercedes Benz coolant (yellow) installed. This should prevent the recurrence of the problem, as there won't be a chemical reaction between the gaskets and the coolant chemicals. This should last for 100,000 miles!! It will protect the other parts of your cooling system best, as well!!!
