OBX header
 

ok i got an obx header off ebay and i installed it and redid my exhasut all the way back from the cat my cat is cleaned out now my exhaust back fires how can i fix this and also my car dosnt run very good now i think cus the timing is a little off or could it be cus the o2 sensor isnt hooked up

Both of those dude. Your 02 sensor has to be plugged up or it just won't get up right.

it will run like crap with either of the two... but i dont think that a loose/non-existing o2 sensor will cause a back fire

The backfire is a by-product of poor timing.

The O2 isn't electrically connected or there is a hole where its supposed to be installed?
It needs to be installed to run properly so the ECU can adjust the fuel air mixture. It plays a large role in how the car runs, its the only thing that feeds back to the ECU when everything else sets up for whats going out of the motor.
Did the new headers bolt right up or did you have to grind anything?
Im also thinking of getting OBX's, my pace setters had to be heavily modded to work and I think ceramic coating will be better than my wrap job.

i dont know my car back fires but its just because of my blow off valve not shutting fully :) nothin better than a little 4" fireball out da back to piss the guy off riding your a$$

you dont have a blow off valve if u dont have a turbo. im assuming you dont bc u bought the obx headers

was jsut thinkin about it... if the o2 sensor is connected, but not in the hole/loose, it may be reading for o2 than what the motor is putting out, thus advancing/retarding the timing, trying to burn the o2. this could also cause the backfire, correct? if im wrong i want someone to say so, dont wanna be putting false info out there.

obx header bolted right up but 2 days laster the head gasket blew outta the motor so i wanna get a turbo motor now