Hello Boggs. These are just my guesses in order.
1. Plugged fuel filter. Replace
2. Weak fuel pump. Replace
3. Weak secondary wiring in Coil; thus, weak(lower voltage) and/or erratic spark when under load. By chance does the car try to spit back thru throttle valve? Replace coil.
4. Low voltage to Coil & ECU's. Replace voltage regulator brushes.
The above are all relatively inexpensive. Best O' Luck!
Richard