Primary Heated O2 sensor heater circuit
 

My check engine light came on, and i found that the code was 41, which is O2 sensor heater circuit, but the problem is that my friends and i changed the O2 sensor, and i have a greddy header, the sensor is new, and we lengthed the wire so that the sensor can plug into the downpipe since greddy header relocated the O2 sensor. I still don't no what is wrong, we reset the ecu, and the same code still pops up. Any one know what is wrong. By the way, the wires were crimped and lengthen, so there is solid connection. But i don't know what is setting off the check engine light.

how many wires does your O2 have? have you used any RTV recently?

4 wires, 2 black, and one white, and one green

you have an EX, welcome to check engine light land. all the EX's have this problem when a header is put on. You need to wrap the header to try and keep in as much heat as you can or it'll throw an 02 slow response code.

jeremy

p.s.: that or one of your extended wires came apart.