If you suspect the pump, hook up your battery charger to the car, unhook the return at the tank and put it in a 5 gal can and see how much it will pump in 1 minute. Make sure your battery charger is putting 14v to the battery and that you're getting 13.5v (or at least the same amt of volts you get with the car running) to the pump itself and give it a test.

I ruined my first efi pump quickly cuz of crap in the tank that got stirred up and I neglected to replace the first piece of rubber hose out of the pickup. Packed the pump full of rubber bits.