Not starting after warm

This sounds very much like a crankshaft position sensor that is failing.

I attached a bit of info about this which explains in more detail. However, the basic point is that the sensor gets hot and it fails which causes the vehicle to shut off and not restart. Then when the sensor cools off it closes the circuit again and the vehicle operates as normal until it does this again.

It is typical that this doesn't set a check engine light because the ECM doesn't know there is anything wrong. It just stops getting an RPM signal from the sensor so it shuts the injectors and plugs off.

https://www.2carpros.com/articles/symptoms-of-a-bad-crankshaft-sensor

Clearly this could be other things but this is the most likely cause.

The cam sensor is a hall effect sensor as well but the engine can run without it so I doubt this is it.

The fact that it is stalling once it warms up tells us that this could be a sensor used during closed loop or the purge valve. Basically when the engine is warming up, it runs off of a pre programmed set of parameters. This means it is not adjusting based on what it is seeing with the sensors. Plus it is not running the purge valve until it is warm.

I would start with removing the purge and seeing if there is any carbon build up or if it looks like the plunger is stuck. If it is then the PCM is turning it on and it is sticking open which puts to much fuel in the engine stalling it.

Normally it will run rough at first then stalls and you can smell fuel. If this is not happening then we may need to hook up a scan tool to see what the o2 sensor are telling us when it is getting ready to stall. This will tell us if it is fuel related which depending on what it is doing can pint us to different areas of concern.

Not sure why I didn't think of that earlier. These pumps are known for leaking internally when they get hot. Before we just replace the pump we need to test the pressure when this is acting up. That will confirm it.

There is still a chance that this is a sensor that when it gets hot that it is reading improperly causing the PCM to not spray enough fuel. This is unlikely as it is probably the pump but I would hate to not confirm it because you need to remove the tank to replace the fuel pump.

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

The PCM controls the fuel pump by sending power through the shutoff switch. It cuts it off when it sees RPM below 120.

So if you cycle the key and do not hear the pump, then either we have an intermittent electrical issue or a PCM issue.

If I may, I have seen fuel injectors and an engine coolant temperature sensor short out when warm. When it wont start can you unplug the coolant sensor to see if it runs? Here is the location. Also the oxygen sensor heaters can short and shut down the PCM as well, lets try the coolant sensor first. Check out the diagrams (below). Please let us know what happens.

So if the pump truly is not coming on when hot then it is wiring or PCM or a sensor (as you and Ken were thinking) telling the PCM to not tie it on.

What happens if you cycle the key a few times when this happens? Does it eventually kick on? May be a good idea to monitor fuel pressure while doing this just as another confirmation it is not building pressure.

I would check for power back a the fuel pump. it sounds like it is going out. Here is a guide check the pink and black wire back at the pump. Cycle the key once the test light is in position.

https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester

Please run down this guide and report back.

I am not following because I can't find where the green/black wire is on the fuel pump. I attached the diagram and I only show a pink/black wire. Do you have the pink/black one and a green/black?

However, when we get the wiring figured out, the fact remains, if you have power to the pump and it is not coming on then I would agree, it sounds like it needs a pump.

That wire should be the feed to the inertia switch. I thought you replaced that? If not we need to suspect that as well. They would fail all the time on these cars. Plus it easier that a fuel pump and I would hate for you to do the pump and it be the switch. Doing the switch and it was the pump is not that big of a deal. Thanks.

Okay. Sounds like you’re on it with the pump. Let us know how it turns out. Thanks