OK... I got some good help here when I was converting my 5-wire VX O2 harness to support a 4-wire O2 when I first swapped in a B16. May car has since seen a supercharged b16, then a turbo b16, and now I have a built b18c turbo.

My problem is that this time I wanted to use the engine harness that came with the b18c rather than the modified one from the VX. Now.... I have the O2 code again.

anyone here know how to connect the GSR engine harness to the VX ECU harness so that the 4-wire o2 works? Should it be as simple as just connecting the GSR harness? If so, then that makes it easy... maybe a bad o2 sensor.

HELP!!