Hey guys, I have a question about the O2 sensor. A few months ago, I bought my 92T with a code 21. I had replaced the sensor with a new Denso 3 wire, but the light was still on (yes, I pulled EFI fuse/disconnected battery). In the meantime, I have been fixing oil and vacuum leak issues and some other stuff. I have finally got everything taken care of except this O2 sensor issue. I haven't bought a multimeter yet to test the Vf signal, but was wondering if the heater circuit could be an issue. I searched and found this old thread:
http://www.supramania.com/forums/showthread.php?22958-What-specifically-triggers-code-21-(searched)
The last post says that the heater circuit is fused. I looked in both fuse boxes, the harness and TSRM, but couldn't find one. Is it actually fused and where is it? What is the likelihood that the heater circuit is the problem?
Let me add, the plastic on the female side of the plug cracked (harness side), so I just pulled the wires out and plugged directly into the O2 sensor. Could the ECU not be getting a good signal because of this? The car seems to run ok and I don't see black smoke or smell excessive amounts of gas in the exhaust. I'll buy a meter soon, but just wanted to see if it could be something easy I've overlooked. I'm hoping it's not a bad ECU. Any help is appreciated.
http://www.supramania.com/forums/showthread.php?22958-What-specifically-triggers-code-21-(searched)
The last post says that the heater circuit is fused. I looked in both fuse boxes, the harness and TSRM, but couldn't find one. Is it actually fused and where is it? What is the likelihood that the heater circuit is the problem?
Let me add, the plastic on the female side of the plug cracked (harness side), so I just pulled the wires out and plugged directly into the O2 sensor. Could the ECU not be getting a good signal because of this? The car seems to run ok and I don't see black smoke or smell excessive amounts of gas in the exhaust. I'll buy a meter soon, but just wanted to see if it could be something easy I've overlooked. I'm hoping it's not a bad ECU. Any help is appreciated.
