I just bought a 2dr 2004 Cavalier. It has around 74k miles and looks like some upgrades were done to it. It appears to have an upgrade dual exhaust. I bought this car from a used dealership, I checked carfax and it only had one owner so I thought it would be a good buy. I also wanted a car to fix up myself and learn as much as possible. My knowledge of car maintenance is amatuer at best. Anyways a few days after buying the car I got a CEL with TRAC OFF light and as I accelerate the car seems very sluggish. I took it to autozone today and it had 6 faults, they saidthat all 6 faultspointed to bank 1 O2 sensor 1. I have one on order now, but I have no idea where it's located. I was told it's rather easy to change, and it requires some splicing...which I can do because I've spliced many wires on F-16 Aircrafts. I didn't write down any of the codes. I need some help on figuring out where it is, will I need to jack the car up, and any safety precautions that I need to be aware of. After I change the sensor, will the CEL turn off on it's own or will it need to be reset by someone? I've been reading around on some forums that it could be caused by the cat converter, but I will change that last if it comes down to that. Thanks in advance.

 

If the code tells you its bank 1 sensor 1 then when you replace that everything should be ok and the code will erase itself. Bank 1 senor 1 is located right on the side ofthe exhaust manifold. Open your hood and it is right there. An lucky enough for you, you do not have to cut any wires. Its a simple unplug and plug in. You will need a wrench to get it out of the manifold. I would recommend spraying some WD40 or pb blaster and let it sit for about 20 minutes. Let me know how everything goes.

 

Thanks for the info Ruffrider
Update: I picked up the O2 sensor today and after driving 3 hours today I had to let the manifold cool down. I was just looking throughout the engine bay and found a disconnected plug. I then found what you were talking about, it's on the bottom of the manifold, so I will need to jack up the front end to get to it. Guess what? The original O2 sensor isn't even connected, it's just put in and the connection is hanging there. The bad thing is that both ends of the sensor is too short to reach each other so I am going to just go ahead and replace O2 sensor which is too short also and will have to splice some wires so that they can reach. I think this is due to when the last owner installed a new dual exhaust kit and just didn't feel like it was important to repair the O2 connection. On aircraft, splicing wires requires the splice to have the exact same wire sizeconnected...on a car, does it matter what gauge the wire has to be or can I use any spare copper wire?

 

Yeah sounds like a lazy mans job to me. What I don't understand is that dual exhaust systems usually come with a new sensor that will reach. But anyway, yes spare copper wire should be fine.