Lurching in Neutral/Smells

I'm new here and don't know a whole lot about cars. My husband and I have been trying to fix up our Forenza to sell it (2004, LX, FWD, Automatic). We replaced the pads, rotors and parking brake shoes (w/new hardware) on both rear wheels and the caliper pins and boots on the driver's side rear wheel. The caliper pins were fine on the passenger side. The caliper pins were seized and rusted on driver's side and managed to get them out. We soaked the caliper bracket in vinegar to de-rust a little (it worked great). We also have had our engine light on for a while and the code I believe was a P0420. We replaced the oxygen sensor upstream. We did all this yesterday and then test drove it and here's what happened.

The driver's side caliper was really tight, we had to kind of bang it on there and don't know why (the passenger side was easy). We replaced the caliper boots only on the driver's side and they were a match for the car and look exactly like the old ones. Both sets of pads were the same for both wheels and actually are the exact same pads that we had previously. The piston was moved back all the way, the pins were properly lubricated and the rotors were cleaned off with brake cleaner prior to install. After the test drive, the rear driver's side wheel was super hot to the touch and smelled like nothing else I've ever smelled (burning??). I read somewhere else that if the caliper is too tight, it could overheat and warp the rotor. Another site said to deal with it for 300 miles and let the pads wear down, so I'm confused there. I don't know why the caliper is so tight on the driver's side, but not the passenger side and were fine fitting before the part replacements.

Concerning the oxygen sensor, I assume, is the lurching while stopped and in neutral. It literally lurches forward while sitting at a light and both of us were shaking when the car did this because it was so forceful. It didn't do this prior to the install of parts. Does this have to do with the oxygen sensor replaced? Does this mean it's the wrong one? We buy all our parts through RockAuto.com and the oxygen sensor was for our 2004 Forenza. I really don't have any suggestions as I've never worked on a car or helped someone work on a car. Thanks for any help :)

I'm new here and don't know a whole lot about cars. My husband and I have been trying to fix up our Forenza to sell it (2004, LX, FWD, Automatic). We replaced the pads, rotors and parking brake shoes (w/new hardware) on both rear wheels and the caliper pins and boots on the driver's side rear wheel. The caliper pins were fine on the passenger side. The caliper pins were seized and rusted on driver's side and managed to get them out. We soaked the caliper bracket in vinegar to de-rust a little (it worked great). We also have had our engine light on for a while and the code I believe was a P0420. We replaced the oxygen sensor upstream. We did all this yesterday and then test drove it and here's what happened.

The driver's side caliper was really tight, we had to kind of bang it on there and don't know why (the passenger side was easy). We replaced the caliper boots only on the driver's side and they were a match for the car and look exactly like the old ones. Both sets of pads were the same for both wheels and actually are the exact same pads that we had previously. The piston was moved back all the way, the pins were properly lubricated and the rotors were cleaned off with brake cleaner prior to install. After the test drive, the rear driver's side wheel was super hot to the touch and smelled like nothing else I've ever smelled (burning??). I read somewhere else that if the caliper is too tight, it could overheat and warp the rotor. Another site said to deal with it for 300 miles and let the pads wear down, so I'm confused there. I don't know why the caliper is so tight on the driver's side, but not the passenger side and were fine fitting before the part replacements.

Concerning the oxygen sensor, I assume, is the lurching while stopped and in neutral. It literally lurches forward while sitting at a light and both of us were shaking when the car did this because it was so forceful. It didn't do this prior to the install of parts. Does this have to do with the oxygen sensor replaced? Does this mean it's the wrong one? We buy all our parts through RockAuto.com and the oxygen sensor was for our 2004 Forenza. I really don't have any suggestions as I've never worked on a car or helped someone work on a car. Thanks for any help :)

You've got an issue where the piston is seized in the caliper. Sounds like you need to pull it back off and see what's going on. As for the upstream O2 sensor, you probably have some other issue. Read the code again and see what you got.