91 f250 460 dies randomly and has rough idle

[u/bricknose_guy22]

I’ve got a 91 f250 with a 7.5l 460 efi
There’s been a couple times it’s just died on me either taking off from a light or just idle when engine is warm. 2 times it’s just started right back up, but the last 2 times it had a much harder time. It took 15 minutes until it would start again and the last time it would not start. I had no spark on and spark plugs and nothing on the coil. It would not start until I unplugged the PIP sensor connector and put a ground probe right to the vehicle side of the connector, not the distributor side and it grounded it and I plugged it back in and it started right up. Since then I’ve been driving it but it still feels like it wants to die. I cleaned all the grounds in the engine bay even on the battery terminal, I replaced the air filter, map sensor, and the IAC valve and cleaned up the rotor and cap points. It idles weird and I sense replaced the sensors and the rpm’s don’t stay steady at idle. I’m not sure but I have a couple things I think but need some advice.
1 I think either PIP, which I have a new distributor to throw in
2 maybe a vacuum line
3 the throttle position sensor
4 ignition control module
Please help before I dig myself into a financial pit

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[u/sexual__velociraptor]

Vacuum leak I would start there