I bought my rx7 last year; everything has been great on it, no probs. I love it, awesome car. Recently though, there has been a strange sound, coming from the catalyic converter (I think).
Whenever I start the car you can hear it, but when I give it some gas, even in neutral, it sounds almost like sandpaper. At around 4000 rpm, the sound stops, when I downshift, its back, strong as ever. There is an exhaust fume smell coming from the front area.

Do you think that indeed it is an exhaust problem, or is it something more serious? I couldn’t see any obvious holes...

91 gxl na

Thanks much

 

Sounds like there is a leak.

 

Really could be any number of things. Exhaust leaks are tricky to find - you have to get the car in the air, start it, and feel around for the escaping exhaust. That's the best technique I've discovered.

Dale

 

Sounds like resonance from the exhaust. Check for loose nuts and bolts.

Does it backfire alot? Thats a classic sign of an exhaust leak.

 

Yea, it does backfire quite a bit... Hmm, would it be safe to start it on jack stands?

 

Sure, just keep it in neutral!!!

The flange gaskets like to blow out all the time. Check them too.