There is a Technical Service Bulletin (TSB) for this exact problem. The fix is to tear the engine apart and replace the piston rings. You might have to pay out of pocket for the repair unfortunately. Chevy’s of these model years are known for excessive oil consumption to the point of blowing a hole through the engine block if not topped up frequently. They are lemons.
U0073 seems to be caused by the OBD reader itself, duscussed here: https://www.subaruoutback.org/threads/code-u0073-after-running-activeobd-app-with-obdlink-lx-bluetooth-scan-tool.427513/
As for P1468, it has something to do with the Diesel Particulate Filter (DPF). The dealer will try to sell you a new DPF, there is a DPF regenration process but it needs a bi directional scan tool. Shown here: https://youtu.be/eFg-N-4fV84
Keep in mind this is what i found searching those codes on google.
Its the splash guard, not urgently important. You can trim off the piece thats hanging. Up to you if you want to replace the whole thing, id be more worried about other undercarriage damage like bent suspension components.
Congrats on getting a new free engine. Kia was sued for this since a lot of KIA/Hyundai were affected:
https://kiaengineclasssettlement.com/
Don’t buy another KIA/Hyundai.
The red triangle exclamation light is called the “Master Warning Light.”
"This warning light stays on for a few seconds when the ignition is switched ON.
The light illuminates continuously if any one of the following occurs. Consult an Authorized Mazda Dealer.
• There is a malfunction in the battery management system.
• There is a malfunction in the brake switch."
That car is ready for the junkyard.
You didnt mention in the post if the timing was set when replacing the chain. Replacing the chain without setting timing can bend the valves in the cylinder head, the 2.4 ecotec is an interference engine.
As for P1682, that seems to be a seperate issue. The problem being the fuse box. This might help you if youre the DIY type: https://www.chevymalibuforum.com/threads/code-p1682-07e8-service-traction-eng-pwr-reduced-service-esc-the-car-runs-awfully.121470/
Whatever broke internally from the bumper tap might be preventing the transmission from shifting. It’d be best to research local transmission shops and call around for rebuild quotes. No one can tell you what’s wrong without tearing apart the transmission.
Hopefully someone else can chime in.
That doesn’t sound right. Go to another independent shop for another diagnosis, avoid dealerships as you might get a similar sized bill. Research shops in your area via Google, Yelp, etc, good luck.
My opinion, take with a grain of salt:
I don’t know how a fuel pump replacement is over $1k, an OE Delphi pump replacement on RockAuto is $350, I find it hard to believe it’s causing all those lights on the dash. Where is the $650 is labor going to? That can be 5-9 hours of labor depending on the shops rate, which too much IMHO. The pump is under the rear seat, it can be replaced DIY in less than 1 hour, 2 hours if you take your time. Definitely get another diagnosis IMO.