Emissions issue with my 4.6

[phatfantom68]

Hey guys, I just got a CEL come on yesterday on the Vic. Got it read and it was P0420 and P0430...

Since the car has 161k miles and the exhaust components seem original, I figure the cats are plugged up. The car is sluggish on acceleration, takes a good amount of power to keep it up at 70mph, and in anything other than highway driving, it gets piss poor gas mileage. The exhaust also has an obnoxious smell when the car is running.

I took a look, and it's got the post-cat O2 sensors behind each primary... so what am I supposed to do with these if I decided to get rid of all 4 cats? Will the car's computer rich/lean out the mixture and cause even more loss of power and mpg's? And of course... the CEL will still be on.

So any ideas? Also, can anyone locally lend a hand cutting these old cats off and helping me fit a test pipe over?

Thanks!

 

[dave89iroc]

to get rid of the cats, you need o2 sims for the rear o2s, or have them tuned out

the rear(after cat) o2s are for cat monitoring only, fronts are for mixture adjustment

 

[phatfantom68]

So removing all 4 cats and unplugging the rear O2's will yield a CEL but no loss of performance?

 

[dave89iroc]

one of the tuners on here will know for sure, but it should be fine

 

[1BADAIR]

if you do some searching you can find what size resister you need online. its like 2 bucks instead of 80