Ford Probe stalls after 15 minutes

Check and monitor the fuel pressure if its within specs fuel pump could be failing if okay clean the MAF sensor with an electronic cleaner CRC -if it continues start testing the ignition system-start at the coil/s

I noticed the fuel rail is leaking after I put the engine back together but it was not leaking when the problem first started happening. I'll fix that first and go from there. The MAF sensor is brand new so I highly doubt that's it but I'll look into that more also. When this first started happening, people were telling me to replace the fuel pump because it might be overheating.. But the car will not start with starting fluid after it stalls. One more thing.. I've only had this car on the road once. Before it stalled out on me, the transmission wasn't shifting into 3rd gear. I was at 4k rpm going up a hill and then it started cutting in and out and stalled. (By the way, I bought the car like this so I don't know what 'normal' is yet)

Update: The ECU is now giving me code 23 which is the right o2 sensor voltage is always below 0.55v. Before replacing the sensor I was getting codes 23 and 24 (voltage never changes). Engine pops when I rev it and idle rpms drop more and more as the car warms up. Does this sound like the distributor is going bad? I've heard these cars have problems in that area.

What do you have for a fuel pressure-have you checked it?

Turned out to be a failing distributor. I just started throwing parts at it until it was fixed. So thank you for the advise. Now I'm stuck on the next problem.. temp guage does not work, fans will not turn on, and the coolant was smoking when I popped the cap. And of course I have no codes to work off of.

Inspect and test the engine coolant temperature sensor and fan relay

Yep. One of my 3 fan relays went bad. After bypassing the relay, I was finally able to drive the car on the road. Unfortunately, I have yet another problem. First and second gear have no power and there is no third or fourth. These transmissions are known for 3-4 clutch pack failure which requires a bit of time to replace. I've tried Lucas Oil trans fix and had no effect. I checked for codes from the trans and got no results. Is there anything else I should check before I start tearing the trans apart?

Have the transmission checked out-