Double check the CPS wire color mark but sounds like it's not that.

I've got one in the barn that often won't start. I rap the main fuel pump a couple of times w/ a screwdriver handle and it goes. And stops ....

I had a car a few years ago that would quit, restart, run for an hour or so; repeat; repeat .....

That one turned out to be a combo:

- the in-tank pump was bad; I replaced and it it would run 2-3 hours before quitting
- I noticed crud in the fuel tank & drained & flushed a bit
- then I pulled the fuel filter and it was clogged. I replaced. The car would run several hours before it quit ....
- Then the main fuel pump failed

Net: I think the bad in-tank pump and sediment and clogged fuel filter contributed to the main pump's demise.

You might also try a spare fuel-pump relay if you have one; or reflow yours.

You'd also be wise to clean all of the grounds: block & body from battery; 3 on intake manifold; strap at the back of the motor.

Note that I don't get the fuel-pump/ key engagement pattern ie. I have cars that run fine where I don't hear the pump at a failed start-up; others where I try to start, it doesn't, I release the key, the pump runs and stops.
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240s: 2 drivers and some parts cars