What's going on everyone. Got a little problem here. My coupe rattles once warmed up, and it rattles only when I'm in drive, reverse, and occasionally on park. Never on neutral. When I'm in the car, it sounds like its under the car. But when I open the hood it gets louder. Also, when I drive a little hard, theres this sulfur smell that arises. A little background, it has 105k miles and where i live theres this rough bump and twice the bottom of my car has hit it no matter how hard i tried to prevent that. Could it be the catalytic converter?

 

If it smells like rotten eggs, your cats are possibly bad or on the way to being bad.

Rattle could be alot of things. Best thing to do is get the car up on a rack and see if there's anything loose.

 

You don't think they're directly related? Could be a possibilty right?

 

They could be, you won't know until you look at it.

 

OP quit guessing and get under your car to inspect your cats. No amount of back and forth on this forum is going to diagnose your issue. There's a distinct possibility you knocked something loose when you bottomed out but until you look under there all we can do is speculate.

 

thanks.