the car isn't mine, so there is going to be some delay in getting some info, so please bear with me.

the car has 130K on the clock, and I don't know if she's had the plugs replaced, but the car has been stalling on her suddenly once it warms up, like the ignition switch is switched off. Then, once it cools down for a night, it runs again. If it only cools down for an hour or two, it will run but only for a few miles before quitting again. I'm thinking a sensor, pcm, or coils, but I'm hoping there's some way to narrow this down a little bit.

 

Are we suppose to just guess what vehicle you're talking about?

 

With little information to go on (year, model, engine, ect...)
I can only offer that if it has stalled there will be codes stored in the computer.

Your local Autozone, Advance Auto, or similar auto parts store can pull those codes for free with a decent amount of accuracy.

You can use that information to diagnose and repair or post more information.

 

Well... I'm sorry, I filled out all that info, and on other forums that pops up with your screen name... ok, it's a 2005 escape v6, she says there are no codes stored, as that was my first thought, too...

 

I'm going to shoot from the hip and say there is an issue with the computer especially if no codes are stored after a stall condition.

I personally would question the lack of codes present. What we don't know is what garage/mechanic used what reader and if there was an issue with it like a broken wire, worn OBD2 plug, ect.

If it were mine and I didn't have an OBD2 reader, I would probably see if I could drive it to one of the parts store I had mentioned and see if they can pull some codes.
If it won't run that long, I would go ahead and have it towed to a dealer where they have all the right tools. You'll pay more for sure, but I'm betting if you chatted with the service manager before taking it there and got him (or her) interested you might be able to work a deal.

You have me wondering -
Is there a specific number of minutes it will run, or does it vary?

I don't know why, but I'm thinking you might want to pull the right side kick panel and inspect the computer and connector. You can also see how hot the computer is getting when it stalls. It should be somewhat warm but not hot to the touch.

Be sure to repost when you have more info.

 

It's been to an independent mechanic and a dealer, neither could help her, so I offered to take a look because she can't get rid of it as it has a Lien on it. I'll ask her if it's a specific time next week whenI get to look at it. One dealership not in my area suggested the throttle body, but would that cool oof then work?

I was also thinking pcm, I was going to drive out until it stopped, then try icing the pcm and seeing if it would start

 

It's been to an independent mechanic and a dealer, neither could help her, so I offered to take a look because she can't get rid of it as it has a Lien on it. I'll ask her if it's a specific time next week whenI get to look at it. One dealership not in my area suggested the throttle body, but would that cool oof then work?

I was also thinking pcm, I was going to drive out until it stopped, then try icing the pcm and seeing if it would start

 

Are you talking about the bcm, then?

 

Does it stall but the ignition stay powered up? Ie she still has all the warning lights connected to a stopped motor with the ignition ON - or does electrical power get cut leaving a blank dashboard? You stated "like the ignition switch is switched off".

This is important, a sensor failure may stop the engine for example but it won't turn the ignition off...

If it is the ignition power being cut then start looking for slop/movement/wear/poor connections in the ignition circuits from the ignition switch out...also the immobiliser connections (remove any aftermarket immobiliser/alarm if it has one).

 

I was planning on noting that when I drive it next week. She's a little older, so I can't count on her remembering all the details.

 

Check the PCM power relay, its socket, and the related specific fuses (and their sockets) that provide operating power to the PCM and other critical circuits.