My stickshift 3.0 1994 Ranger started giving me issues the other day. I drove for about half an hour, parked it, and it wouldn't start back up till it cooled down. On the drive home I had to give her gas when idling to keep it from stalling. My first thought was a bad vacuum leak so I thoroughly inspected my vacuum lines and went through two bottles of carb cleaner spraying all over looking for a leak, no luck. I inspected my EGR and PCV valves but didn't see anything obvious. It sounds to me like a fuel/oxygen ratio issue but I'm not sure where to start looking for the problem.
It will start right up with no issues until it gets fairly hot, I can drive for maybe 15 minutes without any problems. After being warmed up and parked, it will start then idle for 10-40 seconds before the idle gets really rough and the truck will stall. There are no audible or visual changes that happen when it starts to stall out, the idle just get real rough then slows to a stall. Within the last year, I've replaced most of my ignition system including the ignition coil, all spark plugs + wires, and my distributor.
Today I am going to try to use OBD1 to see if it'll tell me anything but I thought I'd ask here to see if anyone might be able to point out any likely culprits or just give me a few ideas of where to look/test next. Thanks in advance for your help!

 

Verify that your CEL light is working. Sensors can fail without setting a code. They just lie to the computer if they don't stop completely working. I would check fuel pressure, both engine not running and while running. Check the sensors regarding temperature, ie Temp sensor, IAT sensor. Unplug the IAC while it's running warm to initially see if you may have a vacuum problem. Dirty MAF sensors can cause crazy problems.