I've replaced the ignition coil
I've replaced the fuel pump
I've replaced the main relay
I don't have air conditioning
If it's 80 degrees or hotter, it will stall after a few minutes of driving
It doesn't smell like rotten eggs, so the catalytic convertor is good
When I try to start it up right after it stalls, it starts up for a second, then shuts back down
It starts back up in a couple minutes
I've spent $836 so far, and I need help diagnosing this problem, or else I'm going to have to sell this thing for parts!