[360jeepboy]

Originally Posted by Leeclipse

The orgional problem was the fuel mix was lean. Lean fuel ratio creates more heat, which was burning the precats. It was actually heat burning them, not the chemical reaction with gas. If it was super rich and to much gas was getting to the cats them they could burn that way to from the chemical reaction in the cats.

This is how it was described by mitsubishis letter sent to their tech centers.

Now either way, both settings may have been rich by some others standards but when compared from the reflash the change was richer.

I agree that after the flash the car ran richer, I'm just saying that it never really ran lean.. I think the problem is cause they put the cats to close to the engine... but what do I know I'm just some guy..

Most of the time the cat will go bad cause there's to much unburnt fuel in the exaust and it gets the cat really hot and melts the inside. It is the job of the cat to get rid of the hydrocarbons but to much is bad... thats why I can't believe people with the reflash arn't having problems yet... but maybe they don't run as rich as I do.