I can’t open my mouth without telling a story, so if you want to get right to the meat, scroll on down to the bottom of this post!
My 93 was having some problems with stumbling and dying a while back. The symptoms were a bit different than yours, but since you’re running out of options…
Mine would die, like it ran out of gas, when the fuel gauge still read 1/8 to ¼ tank. It would sputter if I took a corner fast or if I applied the brakes hard. Going up or down a hill it would also sputter or die. This generally happened when the fuel gauge read below ½ tank. Also I was experiencing pretty crappy mileage. Other than the poor fuel economy, I figured I had a problem with my fuel gauge – most likely the sending unit in the tank (groan).
Turns out there is a plastic baffle in the fuel tank that is supposed to keep the fuel from sloshing away from the fuel pump pickup under hard acceleration. The baffle was cracked and broken, and there were pieces of it laying in the tank. You can’t remove the stupid thing from the tank to fix it – you have to buy a new fuel tank ($ka-ching$). I just cleaned the pieces out and left it at that.
I found one thing in there, however, that I hadn’t expected. There’* a sock filter over the fuel pickup tube that was coated with black spooge (technical term). The screen wasn’t completely clogged, and it seemed to flow OK when I blew through it (yeah, I put my lips on that nasty thing – and I haven’t had a cold sore since). I replaced this little jewel with a new one and re-installed the tank.
I haven’t had any problems with sputtering or dying under low fuel conditions since, and my gas mileage as returned to normal. While the tank baffle was (and still is) hosed, I believe the sock filter was the major contributor to my problem.
If you’re out of ideas, and as a last resort, you might check into changing the filter on your fuel tank pickup. The filter is inexpensive, but you have to drop the tank to get to it.