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My DIC says i need a new downstream O2 sensor. I have found the upstream sensor number was AFS75 delco but i cant find the part number for the downstream. Anyone know?
If you are going to own and work on your own C5, and want to be able to dig in and make the correct diagnosis and not fire the parts cannon at it, I recommend at a minimum getting an inxpensive diagnostic scanner that can read live sensor data or one of the I Phone APPs that allow you to connect to the ALDL (diagnostic port) and blue tooth the data to your I phone.
That will give you the ability to see if the sensor/s is/are outputting the correct voltages.
Are you good with a DVOM ????….if so we can instruct you how to test the wiring and the O2 heater portion of the sensor itself...if not well you may just have to change the sensor and hope for the best !!
Are you good with a DVOM ????….if so we can instruct you how to test the wiring and the O2 heater portion of the sensor itself...if not well you may just have to change the sensor and hope for the best !!
since i dont know what a dvom is, maybe a volt meter, i dont think so. I will try anything once though,
It’s a $20 to $35 part for Christ sake. For the last 40 years I’ve replaced O2 sensors based strictly on the code. Haven’t been wrong yet. And if it hasn’t been replaced recently you are probably better off with a new one anyway.
Last edited by Bubba1951; Feb 1, 2020 at 08:37 PM.
P0161 is saying the heater circuit in Bank 2 Downstream sensor has failed. While a bad connection or broken wire could cause the code it is most likely the sensor itself. An easy way to test wire vs sensor is swap the two downstream sensors. If the code changes to P0141, the sensor is bad. If it stays P0161 the wire or connection is bad.
I replaced my sensors with the Denso brand from Rock Auto. They work perfectly.
I first tried the elcheapo sensors off of eBay. Take my word, don't do that!!
Get this loaner tool from Autozone.
May also need a cheater pipe to break them loose.
Good luck.
O2 sensor
