hanman

I am getting a O2 sensor feedback cel on my 93. It is code #17. It is not the code for the sensor itself.
I assume this means somewhere in the harness? Like maybe a wire that is compromised, but I really don't know for sure. I don't really understand the how's and why's of the "feedback" system. I would have thought if the wire had been compromised, that it would show up as a bad O2 sensor.
My plan is to temporarily run a wire from the O2 sensor directly back to the ECU and attach another wire to run to a multimeter in the cabin. Then I can watch the voltage of the sensor as the car is running. I have already replaced the O2 sensor, just as a matter of routine maintenance. I didn't expect it to cure the problem and of course it didn't.

Does anybody have any information to help me with this diagnosis and solution?
Thanks in advance.

The car is:
93 touring
downpipe/free flow cat/stock catback
intake
new plugs, O2 sensor, eliminated the EGR and AWS, just replaced the turbos

RotorDream

page F36 of the 1993 FSM have fun or if you dont wanna go through all that BS, get a PFC and turn your O2 feedback off! BOOM problem solved!

violentsnail

Or just run without one and have a crappy idle...pretty sure an FD will run without an O2 sensor in closed loop. It just wont run very well, or get very good fuel economy (as if they ever did anyways)

hanman

Yea, I looked at the manual and figured out some things. I tested it with a DMM and I am not getting the results I should have for a good O2 sensor. I am wondering if the plug is bad on the sensor, or if I got a bad sensor from the auto parts store. I would guess a bad connector.
It runs like crap right now anyway, so I am running with it not connected. Now, I have a new problem. It has uncontrolled boost. I am thinking maybe the waste gate actuator is not working. Damn, it's always something with this car.

fd3spr0

Thats possible, I've gotten a few bad sensors and such when they were bought brand new.