I took my car into eds mufflers the other day just to get my exhaust re-welded because it had a couple holes, but i didnt have a cat, so basically i ended up spending 250 dollars instead of 30 dollars, but when they put the cat on, the put the o2 sensor in front of the cat instead of behind it. Now correct me if im wrong...but its supposed to be BEHIND the cat, no? Now i have a check engine light, and have an appointment with them tomorrow.

 

one in front and one in back usually

 

yeah thats what i figured, but they made it so that both of them are in front.

 

dumb ***'s . Its definetly supposed to be one in front and one in back

 

if o2 sensors are in front of cat and behind it....what is the one connect to header?

 

could that be an EGT probe?