Strange behaviour

[Tim Sexton <tsexton@sc.younglife.org>]

Hello,
    My 87 5kcstq 5spd has started doing something strange.  The car
starts and idles fine,  but when I apply the gas pedal it tries to die,
and then catches itself and goes like it should.  The problem seems to
be worse when the car is warm,  and last night I could barely get it to
move without quitting.  It finally stalled and took a long time to
restart.  I also had to hold the gas pedal all the way on the floor to
make it stumble to life.  It acts like it is starving for fuel, or like
a dead accelerator pump on a carbeurated(sp?) car.  The fuel pump was
replaced recently, and I don't have any vacuum leaks. I also checked the
ignition system and pulled the fault codes which revealed nothing.
Anyone have any theories?  Any advice would be greatly appreciated.
Tim Sexton
Co.Springs, CO