Do they just tell the PCM the condition of the cats or is there more to it than that? Do the sims just constantly report that the cats are good?

 

That's right,you won't miss them at all.

 

You pretty much hit the nail on the head. COntrary to what ppl will tell ya, they are for emission purposes only. The truck will run fine without them.

 

Thanks for the info;I might go with headers someday.

 

Arent they for cat efficiency and cat-over-temp?

 

Yup .. .still emissions crap though. That verifies the cat's are working in an effecient manor.

 

So, in my case, I know one of the heat sensors or something to that effect is bad in the rear sensor. All that will do is cause the SES light to come on, right? They don't adjust fuel or anything? What do the front do out of curiosity?

 

The front's are the ones that adjust fuel. Those you want to be in good working condition.

That's correct about the rears, as long as the code says bank x sensor 2, then I wouldn't worry about it. If you DO notice poor performance, it might be a cat going bad.

 

Cats were just replaced with Dynatech system recently.

 

i have the simulators on my truck...the truck runs fine with or without them, you just don't worry about having ur SES light on with them