When I first start my 2007 4wheel drive (6cyl) truck I get what sounds like an exhaust sound. As the engine warms it goes away and it is worse during cold weather. They replace the manifolds and gasgets under warranty, but that did not fix problem. The dealer claims it is noise from
purge valve at charcoal cannister. anyone have this problem. Even though I have extended warranty they will not fix because no problem shows up on system. BE GLAD WHEN HUNTING SEASON GETS HERE!!!