Engine stalls and hard to restart

I have a 1995 GMC Sanoma, 2.2 Lt, 4 cyl, 5 spd. It has about 130K miles. Each day I drive it back and forth to work (about 30 miles one way). About 6 months ago I noticed that at about 5 miles into my drive to work it would stutter but then catch itself and go on the rest of the way with no problems. On the drive home it would do the same thing at about 8 miles into the drive. This didn’t really bother me until one day instead of stuttering it stalled but I could restart it right away while coasting. It had steadily gotten worse to where I had to pull over on the side of the road and restart because it wouldn’t restart right away. Nowadays I hardly drive it at all because I’m afraid it will stall and not restart at all. I have replaced the air idle control, fuel pump relay and the positive battery cable. The symptons now are basically the same but different, I can start it (anytime, morning or evening) and it will idle fine for about 5-10 minutes. It will then start to stutter and try to catch itself, the idle will then rev up to about 1500 and then come back down and stutter some more before stalling. After that it will not start back up until maybe 10 minutes after, (it acts like it is not getting any fuel) but once it starts it runs fine, I drove it around for about 20 miles and it ran real strong. The next day it went through this same cycle again.

I have a 2002 GMC Sonoma. Sometimes when highway driving for about 50 minutes, the car will loser power, the voltage meter will drop, and the car will slowly quit (the dash idiot lights will come on)and the car will die. I can get it started, and usually it runs fine. This happens about once a week. When running, it runs well. Also, some difficulty starting. I have replaced the cad. Converter, the alternator, the fuel pump, the crankcase position sensor, the engine temperature sensor, and had a tune up. Any ideas?