Plate opening sound at start-up

[tim connell]

Hey, I have a 96 7.3, with about 105,000 miles on it, and for 2 winters i have had a problem, and every summer i promise myself i will check it, and here it is fall and now i'm checking. In the summer when i start my truck, in 5 to 10 second i hear a plate or metal sound that sounds like something is opening up. No prroblem, but in the cold weather I donot hear this and the truck bogs when it shifts ito another gear (automatic). I have found that if i let the truck warm up for a LONG while then shut it off and start it again the plate opens, I can hear it. Also if i plug the truck in(and my electric meter glows) sometimes it will open and some times not. I have a 3" down pipe and dual 6" side pipes AKA, stacks under the truck, and maybe this is why I can hear it. any thought would be helpful.

Thanks!

[Gruss]

Sounds like the EBPV is opening up. Do a search you will find lots of info.