Rep Power: 452

Well, this morning I had to drive a friend to the airport and when I went to turn my car, it was making this wired rattling noise underneath, well it only happened when going really slow and reving it. Well after I was done at the airport, I went back to the shop I had my exhaust work done, and they hit my cat converter, and said it was dead. when they hit it, all this **** inside rattled around. Well, the cat converter I got from them was a high flow one that I got about 1 yr. before, and they said that these things dont go out that fast. He said that I also might be running to lean? Whatever the hell that means. the funny thing was, the check engine light never came on. Well they replaced it free of charge, but what do you all think the problem might be?

 
Rep Power: 0

Running too lean means too much fuel over air in the AF ratio. Did you try resetting your ecu after you installed it? usually balances out the AF ratio.

 
Rep Power: 452

how do you do that?

 
Rep Power: 304

isnt running lean too much air over fuel. i think running rich is too much fuel. and it doesnt make any sense to reset the ecu after you install a cat.

 
Rep Power: 0

Yes that was it.. My fault.. rich is too much fuel, lean is too much air. Just that shouldn't need you to reset the ecu but if thats the case and its running to lean then ressetting might be the cure.

 
Rep Power: 284

I hear stuff bouncing aroung in my cat when i rev sometimes. I tried to get it all out by running with the exhaust off for a day but the sound came back after a while.