Good evening fellow Bricker's. I bought a chip that claims to improve HP 15-20 on Ebay. Looking at the wiring diagram for 1993 940 non-turbo, it states the green is signal, black is ground and pink goes to fuse # 11. At the O2 sensor, the leads are black, red and white. How can I determine which lead on the sensor goes where. The chip only has red and black lead, red to signal and black to ground. I hooked the red lead on the chip to the red lead at the sensor, started the car, it stumbled at idle, drove a few miles then the check engine light came on. Arrived back at home, disconnected the chip, no more check engine light or rough idle. Any thoughts on this chip. Thanks to all.


Darryl