So after my y-pipe install my front 02 sensor keeps tripping up, and today i got a 0303 with an 1001 and a 0901. Which are the heater units for the o2 sensors left and right. So i was going to order an 02 sensors, but are all the 02 sensors interchangeable? At oxygensensors.com there are 3 wire types which i was going to buy for the front and back when installing y-pipe seem to be 3 wire but want to make sure. I might just wanna order 2 just for saftey down the road if they all are matching. Also does a CEL from the front left 02 sensors slow the car/engine down?

 

BuMp

 

You want the three wire one. Get the OEM one so you don't have to hack the harness. Also, when the upstream sensors aren't functioning properly, your fuel economy and performance will suffer.

~THT

 

so interchangable from the front two in y-pipe to the last one behind cat?

 

No, the one behind that cat is a 4-wire sensor.

~THT