I was on the wrong site and posted this earlier elsewhere. Pointless. Anyways, could somebody please provide some clarification for me here? I have a 1999 2500 v10 CA exhaust. I just recently replaced all 4 oxygen sensors and ever since have had nothing but problems. In the service manual it says there’s 2 upstream and a pre and post catalyst sensor. The truck wiring has plugs for 3 (grey plugs/upstream?) and 1(black plug/downstream?). So, is there a difference in the sensors? I ordered 3 up and 1 downstream, should I have worded my order different and would I have gotten a different sensor if I did?
Also, I noticed that one of the sensor wires on the truck side have some breakage just before the plug. Is it possible to fix the plug? I know you’re not supposed to solder it so does that mean it just must be replaced? And lastly, is it important that all four sensors be the same brand? How much of an impact does manufacturer make when it comes to o2 sensors. Thanks in advance sorry if these a dumb questions.

 

What problem are you having, and what brand sensors did you buy?

 

Ngk, I believe. I am attempting to get my truck to pass smog. It ran great-ish! I took it to smog shop and it passed emissions but two monitors needed to run for it to pass, the o2sensor and evaporate monitors, I believe. I drove it and drove it and nothing. My fuel pump goes out and while I’m at it I decide to change the o2 sensors. Ran great for about two days. Now, whenever it warms up it runs like crap. Wants to sputter, hesitate and just in general run like ****.keeps throwing code p0144. When I clear the code it doesn’t come right back on, but it wants to. I was reading that your not supposed to repair oxygen sensor wires, which I did do with some liquid tape. The o2 sensor after the cat has frayed wires on the truck side just before the plug. Idk. Thanks a lot for your help, Lynn

 

If you have wiring issues at one of your sensors, that would account for the code. That one is for bank one, sensor 3.... I have no idea what your exhaust looks like though......

 

I figured as much. Is there a way to fix the wire though? Or do I just have to replace it? I probably gotta just replace it since I tried to liquid tape it up already. My exhaust has 1 on the left manifold down pipe 1 on the right. Another sensor in the front of the cat and one about 4” behind it. Left side Exhaust pipe extends over to the passenger side and both go into the cat, cat has one out put to a 4” straight pipe.

 

You can repair them by solder or a heat shrink but connector. It all depends on how much wire is left. You can buy the connectors on Rockauto or any parts store

 

Thank you moparfanatic, it says specifically not to solder them in the service manual. I can’t do butt connectors cause it’s right on the plug. What about splicing it? Just wiring the sensor straight to the vehicle side of the plug. It’s not ideal, but I live in the mountains and pick a part ain’t exactly easy to get to. Is there any known issue about this?

 

Well it's not working right now anyways so you might just as well try soldering it as it's at the plug end. O2 sensors actually generate voltage based on the difference in O2 concentration between the outside and the exhaust gas. Soldering close to the sensor supposedly throws that off as the actual wiring is used for outside reference.

 

I have soldered plenty of O2 sensors and never had an issue personally. But if it makes you feel better you could hard wire it to the vehicle

 

Sensor three would be the one right in front of the cat then. Is that the one with the bad connector?