That's what I figured. I've already taken the EGR valve off once and tried to clean it, and the engine threw a code again. The service dept. said the vavle should still be functional though... What is this seafoam stuff, and where can I get it? Also, you're saying that I should take the top half of the intake manifold and EGR off and poke around in there with the bottom half still on to clean it out? Just want to be clear.