About three months ago I started to hear an exhaust leak. Now it is horrible. It only leaks when you floor it or are at full throttle. Some have told me its my exhaust others have said its my motor mounts which are allowing my exhaust to flex and open up. My car has 114,000 mi if that helps any. Thanks for the answers.

 

Check all of your bolts throughout the exhaust system, from where the header bolts to the cat, all the way to where the axle back bolts to the bpipe. Try to feel for air leaks while your car is running...jack it up, start it, and get underneath.

 

If they say it happens when the motor moves, it could most likely be the donut gasket between the exhaust manifold and the cat. I would check there first.

 

Check your tire pressure too. That could be it...j/k when yor under there check the connection for soot outlets between the seals you'll see it. It'll be the black part where it looks like something is getting through. Replace the gaskets that need to be replaced and make sure everything else is snug. Unless your car has a swap in it, I doubt it is the motor mounts.