I recently purchased a 85 runner which has an 88 ecu installed by the previous owner. It is throwing codes for a o2 sensor. I installed a new exhaust and o2 sensor using a front pipe for an 88 so the sensor is in the right place but the sensor wire is/was routed up through the shifter boot and upon inspection I found that wire is only half-assed to the ecu. I am having difficulty figuring it out and I only have the 85 fsm. I am hoping that someone here might be able to lead me to the correct wiring diagam for an 88 ecu. I am getting pitiful fuel mileage and need to start here. Some direction as to the correct wire path would help also. I plan on cutting a new hole above the transmission sized for the rubber grommet that came on the new denso o2 sensor. Thanks for any help!

 

You should try ncttora.com to find a service manual, I believe the one on there is 1988 specific. With 02 sensors, they are a shielded wire, and its common for people to accidentally crimp some of the shielding in with the wire, which will cause a check engine light for it. If you think the wiring job is questionable, re pin a new wire from the ECU to the 02 sensor

 

Thanks, I'll try that site. Like I said The wiring is half assed to the ecu. It has been jumpered to the wiring coming from the ecu and a couple of wires are detached without any signs of where they go. Its a bit more than a pinched wire but thanks.