fbody4everyone

Im replacing all 4 of my o2s on my 02 ws6. got headers recently

went to parts store to get new ones, and was wondering what the diff between upstream and downstream? he ordered me 4 of em, will it matter which one i plug into the connection, or does it not matter? thanks

fbody4everyone

also, can i just plug the rear o2 holes since i dont have cats anymore?

omc8

iTrader: (7)

If your cat delete you don't need the down stream O2s , just the front. Iirc the right upstream is specific, the left can be flip flopped. Just make sure you bought a good brand AC delco is best. Bosch is not recommended.