Alex, maybe a bit late, but as I've mentioned here before Toyota of South Atlanta via their website has incredible prices on OEM parts.
Throwing parts at it is a bad idea. Put a scanner on it and see what the computer wants the fuel pressure to be and what the sensor is telling it it is. KOEO is it in the 50psi range? Does the engine start? What is it reading with it running? The number one rule is to look for irrational numbers in the data stream then find out why they are off. Honestly, working on any modernish car without a scanner is just wasting money and time. Might as well be using slip jaw pliers and a Swiss Army knife to Try and change those parts….
It's there. Can low voltage cause engine light, and all those codes? My past experience with bad batteries was "no start" condition and never any codes.
I have put a scanner, but I am not smart enough to get deeper than reading existing codes. It has a "Live View" mode, but to be honest I just don't know what to look for.
you need a tactrix obd2 adapter, and a pirated version of toyota techstream, on your laptop. then you have the hardware and software to diagnose issues, and make changes to the auto via software. lots of toyota forums have the know how for this. Ski
Would this give me more accurate troubleshooting ability vs reading error codes with an OBD2 scanner. That is what I have: https://www.harborfreight.com/zr8s-obd2-code-reader-with-live-data-57667.html
Is this how to test the battery? Connect the multimeter to the positive and negative battery terminals. If you don't have a voltage of around 12.6 volts, you may have a bad battery. Now start the car, and look for a revised voltage over 10. If your voltage drops below 5 when the car is running, it is bad and should be replaced