[joshuakittery]

I have a 1999 Durango 4x4 with the 5.9, my check engine light has been on since I bought it, I originally have a P0132 and P0138 on bank 1 sensor 2. I also had a P0308 misfire on the 8th cylinder. I replaced all of my spark plugs and the misfire went away. I checked the bank 1 sensor 2 with my multi-meter and I just assumed that it was working but I may have a bad cat. So I did the non fouler mod to the sensor after the cat. The check engine light went away for a day to work approximately 28 miles. The next morning about 5 miles into the drive the check engine light came on again. Now I am getting P0132 and Po135 on bank 1 sensor 1. I am unsure why but I was hoping someone on here would know a little more than I do. Do I just need to replace the O2 sensor on bank 1 sensor 1 or have I done something with the O2 sensors by adding the non fouler to the sensor after the cat? This is my first post and I am a noob so please if you can help I would greatly appreciate it.

 

[joshuakittery]

I just took a look at my truck and up to this point I have always assumed that I had 3 o2 sensors but apparently I can only find 2. 1 directly before the cat and 1 after the cat. I looked at the 1 before the cat and all the wires seem fine. Are there more sensors or are these the only 2?

 

[Tymont]

If your cat is bad you should get a code for it. I would replace both the o2 sensors since they aren't very expensive.

 

[joshuakittery]

Are there any specific o2 sensors that would fit my durango? As cheap as it may sound I have a junkyard here that will let me have one for free. I have a multimeter to help test the new used one. Is there any particular year make model and engine size to look for?

 

[Tymont]

How are you checking for proper operation of the O2 sensor with a multimeter? There's more to an O2 sensor than just is it putting out a voltage. It's also how much voltage and how fast it cycles. The only true way to check it is to use a vehicle programmer that can monitor real time data points.
You can get the O2 sensors from a junck yard. But you're taking a shot in the dark as to whether or not you're getting a good one.

 

[joshuakittery]

I check the resistance in the heater core part of the o2 sensor, if I get any reading then I call it good, I let the computer decide whether or not the actual sensor is good or bad. When the light first came on it was the rear sensor. I pulled it out and checked the heater core resistance and I got a reading. I put it back in with the non fouler mod, the light was off for a day and then came back on. The light now says that the entire front sensor is not getting a reading period. I removed the non fouler mod yesterday and reset the pcm. The light came on as soon as the truck warmed up and it still says that the sensor before the cat is not working. I checked the fuses and checked the wires to the first sensor and everything seems intact. I have not been able to get the first sensor out yet to test it.