While pressing down on the accelerator there is a buzzing rattling noise coming from under the dog house. There are two black modules mounted on the drivers side of the dog house. I am not a mechanic so I do not know what these items control. This is a chevy P-30 with a chevy 454 4 bbl., 1987 fleetwood pace arrow. My chilton book does not show me anything in this regards. What could these be? help! I am stumped.

Sorry can't help you.Call the dealer ask for a service ADVISOR

I had the same problem with my 8.1 liter, fibrations. It was the heat shields around the mufflers. I punched a small hole in the bottom of each heat shield and took a piece of tie wire through the holes and twisted them together putting pressure on the heat shields, end of fibration. Hope this helps Bill

A buzzing or rattling sound could easily describe spark knock, which comes from too low an octane fuel or a poorly tuned engine. Ignition problems were not uncommon on that vintage engine. When did you last check/change the spark plugs? Have you changed brands of fuel lately?

My first thought while reading your post was "heat shields". I've had a similar situation with an older RV. If thye are in good enough condition you can attempt to secure them. But if not you can do like I did and eliminate them...