i pulled my catilytic converter off and kept the o2 senser off the back of it and mounted it back in my exhaust. since i have done that my jeep has dropped from 12.5 mpg to 9mpg and my check engine light is on. has anybody else ran into this problem when they removed there cat? i had to pull it off from the cat back when i was fourwheeling because it got clogged up and lost power and would hardly run. can i go to a parts store and get a universal one or does it have to be round like the one i pulled of? one for the jeep is $150 and universal's start a $30.

 

When you pulled your cat (Federal Offence), you dinked the exhaust levels that the computer needs to manage the engine correctly.

Please replace your cat with a proper unit as our Jeeps don't need any more excuses to have them regulated more.

Once you replace your cat, your engine management will start working again and your MPG will go up.

 

so pretty much replace it with the $150 dollar one it calls for?

 

Any cat should work to fix your CEL issue. You will need to make the universals fit by welding them in place but they should still work