Exhaust Leak

[thebigo432]

So today i pulled my pipes down so that i could check the welds where the cats were replaced. When i pulled the pipes down i could see some signs of leaking exhaust and i was hoping that welding up these areas would fix the leak. Now that they are all completely welded back up, the leak is still there... I cant seem to find it and im getting rather irritated. :cussing: Now the thing is the leak is only evident during acceleration, i can hit the peddle and hear the leak, but when i keep at the same speed and less throttle it is gone. Any other ideas what could be making this noise, besides an exhaust leak.

[PHATSPEED7x]

Bad exhaust donut?

[Firestrike87]

So today i pulled my pipes down so that i could check the welds where the cats were replaced. When i pulled the pipes down i could see some signs of leaking exhaust and i was hoping that welding up these areas would fix the leak. Now that they are all completely welded back up, the leak is still there... I cant seem to find it and im getting rather irritated. :cussing: Now the thing is the leak is only evident during acceleration, i can hit the peddle and hear the leak, but when i keep at the same speed and less throttle it is gone. Any other ideas what could be making this noise, besides an exhaust leak.
It sounds like a pinhole exhaust leak, the exact same damn kind I've been chasing for a year or so. Unfortunately for me I don't have easy access to a welder but what I've done and might work for you too is crawl under your truck right after you start it before it gets warm, and you may have a couple of minutes before you can't touch the pipes, and feel around for air being pushed out through a hole to locate them. I feel your pain man but you gotta just keep on looking. Now if it is fairly loud which it doesn't sound like I'd say doughnut gaskets too.

[thebigo432]

Well i dont have a donut gasket anymore, i got headers and the collectors aren't leaking, and it isnt leaking around the header flange so i ruled the key areas out, so im guessing it a pinhole. Do you think if i sea foam it the pinhole will show with the smoke if i put it under load?