[cnntnsxty@aol.com]

Heat riser is okay checked it cold it was closed with spring pressure warmed her up and it opened after awhile. While it's cold giving it a quick shot of throttle will cause it to open and then snap back closed when you let off but that's not the sound I'm hearing. I can't believe I haven't figured this out yet, I'm sure its something simple. I will triumph over this machine eventually but for now she's got me outsmarted. I know I've heard this happen on other trucks years ago as they would take off from a stop so I know someone else has experienced this. Going to go crawl around and check to see if I can find anything that looks like it's been hitting. Thank y'all for the ideas of what to look for, its appreciated