I am new to the site i just want to give a thumbs up to everyone posting you guys all know your stuff and are a HUGE help to people like me who just bought their GP last week.When i bought the car i knew that the intake manifold gaskets were a common problem with the 3800. This afternoon sitting in traffic in Boston the temp started creeping up but only got to about 210 before i got back on the highway and it was fine. A few other times when i got off the highway i caught it creeping up again but not quite so high. I am suspecting that i need to replace upper plenum and lower gaskets but just wondering for any adivse of possible performance upgrades while im in there or maybe if i am missing the diagnosis here. I plan to pressure test the system in the morning at work but any advise would be much appreciated! Thanks everyone!
