1991 nissan maxima long crank then putts for 6-8 seconds then die

1991 nissan maxima long crank then barely putts for 6-8 seconds then dies. If during the putt putting I touch the throttle pedal it dies. when I first got this car (in this condition) it had quit on the highway and the owner replaced the distributor, cap, wires and plugs, It did not help. It was then able to start and it would build up to a good idle but you had to feather the throttle lightly to get the car to drive without stalling it. I pulled the fuel hose off at the filter and there is good fuel pressure. I cleaned the throttle position sensor (contacts corrosion) but this did not help. What could be the problem?