What have I gotten myself into?

You might be missing some of the stored DTCs.

Not all OBD2 scanners are Toyota hybrid compatible, which device are you using to read those DTCs with?

Here is the workup for DTC P1116 : https://share.qclt.com/%E4%B8%B0%E7%94%B0%E6%99%AE%E7%91%9E%E6%96%AF%E5%8E%9F%E5%8E%82%E8%8B%B1%E6%96%87%E6%89%8B%E5%86%8Cpdf%E6%A0%BC%E5%BC%8F/Repair%20Manual/04pruisr/05/2054m/cip1116.pdf

Here is the workup for DTC P1121 : https://share.qclt.com/%E4%B8%B0%E7%94%B0%E6%99%AE%E7%91%9E%E6%96%AF%E5%8E%9F%E5%8E%82%E8%8B%B1%E6%96%87%E6%89%8B%E5%86%8Cpdf%E6%A0%BC%E5%BC%8F/Repair%20Manual/04pruisr/05/2054m/cip1121a.pdf

 

See a shrink about your masochistic tendencies ??
(Mostly not a joke.)

If the traction battery is bad AND the engine has worn out bearings and maybe a leaking head gasket.......I would consider it worth LESS than nothing. Might get a little out of parting it out.

 

replace the odd size tire with an even one.

all the best!

 

2007 with 290xxx miles
I'm not afraid of miles.

Codes 1116 and 1121
Codes P1116 and 1121 ae no big deal and are heat storage related. 16 is temperature sensor and 21 is flow control valve. I think both can be triggered if the computer thinks the system performance is weak due to clogging. Throw in half a gallon of coolant and makes you wonder if previous owner was working on it.

Engine idles rough has loudish ticking/tapping noise
And of course, that half gallon of coolant could have an even more evil background based on your description of how the engine is running. There could be engine related problems like a head gasket. But I've also had horrible ticking noises come from a misfire. You'll know more when you get techstream. You are going to do that right?

Runs poorly, appears to be running the ICE constantly
HV / Traction battery will not charge
Traction battery was replaced by Toyota in 2015
If the HV battery was truly replaced by Toyota in 20015, with a factory new battery, odds are slim you have a battery problem. Slim, but not zero. The electronics section of the battery would still be original 2007 equipment, which means there may be corrosion issues in the ecu harness plug. These issues will become crystal clear when you get techstream.

New 12volt battery May of 2019
Sweet. Make sure it's fully charged so you're not chasing your tail.

VSC Brake light etc... lit up on dash...
Hate that and hate what it possibly means. Did I mention that will become more clear with techstream?

Combination Meter Display non working /reset by disconnecting 12v
Combo meter....nbd, seems to be a fairly common occurrence at that age. As long as it continues to only be an intermittent problem, you can fix it when convenient.

One odd size tire on the rear
Yikes. Obviously something that should be rectified prior to making it a driver, but should have no impact while parked in driveway while performing repairs.

Previous owner replaced one rear hub assembly
Good for him, and you, as long as he didn't tear anything up.

Has a partial bottle of pink extra life antifreeze in hatch area
Makes you wonder what the other half gallon was used for. What system needed it …..


Did I mention this is like the perfect time to have Techstream...there are no third party apps that can even come close. It's like the difference between having a neighbor look at you and give you a medical diagnosis or going to a specialist and having a full body MRI performed.​