PontiacBonnevilleClub.com

Does the 3.8 engine have a Heat Riser Vavle or anything comparable?

http://autorepair.about.com/library/glo ... ef-301.htm

Definition: A control valve between the exhaust manifold and exhaust pipe on one side of a V8 or V6 engine that restricts the flow of exhaust causing it to flow back through the heat riser channel under the intake manifold. This aids fuel evaporation and speeds engine warm up. A heat riser valve stuck open will slow engine warm-up and may cause hesitation and stalling when the engine is cold. A valve stuck in the closed position will greatly restrict the exhaust system and cause a noticeable lack of power and drop in fuel economy.

Thanks

No it doesn't. First I have heard of it though.

My old Somerset had something similar. It had a round protrusion in the exhaust manifold heatsheild, and a tube connected to it ran to the intake. A valve would open and pull in air heated by the exhaust manifold for the same purpose. Although my valve was stuck open and it burned up a piston, twice.

Does it actually pull exhaust into the cylinder? Sounds like kind of like an EGR on a bigger scale??

No, a heat riser is a device that re-routes exhaust gases inside the manifold to heat the intake manifold/air intake. I have one on my Rambler, which is stuck. When the car warms up, the flap moves back the other way to let the exhaust freeflow again.

Great, thanks for the info.