My friends and I just installed a DC header and the check engine light came on. We had to cut the wire from the O2 sensor to the header because the nut got stripped. When my friend put the wires back together after we got the sensor off the old header, the engine check light was on. So we swaped the 2 white wires and still there is a check light. Could it be the O2 senor that is messed up? Or the wireing? Just letting you guys know, the car is running fine and loud. Headers did make a difference. Even if it is DC. Please help me.

 

When I put a header on my Integra, that is EXACTLY the problem I had. I would go and get it hooked up to a diagnostic computer and find out what the code is....but I am willing to but its the O2 sensor.

 

It takes some time (three start and warm-up cycles) to clear a code, so it could be possible the error is gone, but the light is still on.

Did you try to reset the ECU to see that the light stays off?


Siepel

 

Reset first the ECU. If still you get the fault, try the O2 simulator.

 

The O2 sim is for the sensor in the cat. The one in the header is the PRIMARY sensor that the ECU needs to run the engine. You should not be trying to alter the signal from that one.

 

Yes, don't do the O2 sim on this, the engine uses this one to determine the A/F ratio and add or take out fuel...I'd bet it is your O2 sensor as well, try hooking the wires up the way they should be and clearing the ECU, then see what happens...the code wont just go away, you have to clear it first

 

Yeah, I did reset the ecu. We unplugged the battery and everything... But as soon as i started it up, it came back on. I'm wondering if I should just buy a new o2 sensor...what do you guys think?