My car is a 2012 Chevy malibu with just under 120,000 miles. At about 104,000 it started stalling when you went to start it after driving a short time. Like 10-15 minute ride to the store, runs fine. Shutoff at the store, In and out in 5 minutes and it starts and immediately stalls. Next attempt doesn't sound it even tries, like it's not getting gas. Auto parts store scanned it and had a codefor a bad VVS and possibly a throttle body. Replaced vvs, no check engine light. Still doing same thing, replaced throttle body. Had to take it to a shop for a relearn. So not wanting to start after driving a little while. Took it to the shop.
In and out of the shop for months. Replaced fuel pump, rear fuse box, both VVS. Always ran and started fine for shop after replacements. Still getting same issue.
Then finally it wouldn't start at all. I Replaced coils, plugs valve cover gasket. No start. Took it to another shop. They got it started but still couldn't figure out why it didn't want to start after driving fur a bit. Had it it towed to an electrical specialist. Tow truck driver started car and drove it on the bed, then off the bed.
When the shop opened, the wouldn't start for them. Eventually they found melted wiring in the rear wiring harness and some bad connectors. Replaced wiring harness, rear fuse box and fixed some bad connectors. Did complete relearn, idled and shifted right after finally.
About three or four months later it's doing the same thing again. Took it to the shop that got it running. They had no problems with it. Only thing they says is it could be a bad key fab as the remote is pretty much dead abs won't unlock the doors, just the trunk. Getting a new one made when I can but not confident that will fix it.
Stopped at the store on the way home from work. Came out and wouldn't start. Decided to wait it out. After about 2 1/2 hours decided to call a tow truck. Wouldn't start when he got there. Loaded it up, dropped it off. Tow truck driver got in after unloading. Started on first try. So I took the car home.
Needed something out of my car about 10 minutes after getting to work. For fun I tried it, started and stalled. When I left shirk 8 hours later, it started up fine.
Has anyone had an issue like this, Note, I did hear of someone that bought some bling to go around the keyhole that had this issue but I do not have any bling on it.
I've seen that kind of thing happen (works when cold, quits when hot) with a hinky crank position sensor - just recently in fact with a family member's car. So you might want to test that.
Of course the wiring harness problem you experienced brings with it the possibility of deep electrical system problems. Those cars are also infamous for engine problems.
Most repair shops rely too heavily on their scanners and when the data they're seeing doesn't point them in the right direction they get lost.
Assume during a "crank no start" they checked to see if the rpms were being displayed in Live Data to make sure the crankshaft position sensor was working.
And that one of these guys tried spraying some starting fluid into the intake to make sure this isn't a fuel starvation issue.
And they checked for a vacuum leak or if the Evap Purge valve was sticking open or if the IAT and ECT temperatures are correct and not causing an "engine warm/no start" problem.
And they ruled out the theft system.
After all these assumptions (hopefully correct) ((I would check for myself)) maybe move onto using a test light to check for power on both test tabs of every fuse that either provides power to the ECM, BCM, or to the Engine Control sensors during your crank/no start.
Then check for the 5 volt reference from the computer (probably at the IAT sensor because it's easy to get to) just to make sure the computer isn't acting up and causing the crank/no start
((Link to these images)):
https://f01.justanswer.com/NikVee/11f7815a-7223-4711-9be2-448fcf08b7b0_Power_Distribution.pdf
One other thing that I had fixed. The front main seal started leaking at about 100,000 miles. Had the second shop replace the seal around 110,000 miles or so.