Engine shuts off after running twenty to thirty minutes

When it cuts off, does it restart right away or do you have to wait a bit?

I am thinking we need to monitor fuel pressure while this happens just to make sure it is not dropping. Then I am thinking the Idle Air control valve could be your issue.

Also, this could be a PCM issue but we need to start eliminating things before we get there.

https://www.2carpros.com/articles/idle-air-control-valve-service

It will start right away but then hit shuts off sooner than it did the first time and it only does it twice and then it won't start for quite a while.

I am right now going to try to my best to give it a fuel pressure test I wanted out I went out and rented a kit and hopefully I can get some from that. Because I got nothing.

Also and not this has anything to do with what's going on for sure, but I do have a disconnected but seems to be vacuum hose coming from the transmission from top of transmission. I don't know if that's an issue or not, but it's not connected to anything. looks like it's been cut off and I have no idea where it goes.

If by vacuum hose, you mean a rubber hose that they use for vacuum line, then more than likely this is a vent line.

I looked for any vacuum lines that may come off the transmission but didn't find any. Plus transmissions don't require any vacuum lines so I am sure it is a vent.

If you want to get a picture of it, maybe I can recognize it. Let me know what the fuel pressure is and we can go from there. Thanks

I will send you a pic of that tomorrow. I didn't get to do the test because of a drained battery that is only 2 months old.

I'll be back there tomorrow morning and then the battery should be fully charged. I think it has something to do with the alternator, and the fact that the van was sitting (stored) for 10 years.

Oh my. Yes. If it has been sitting that long then we would need to start there. Let me know how you make out and we can take the next step.