[rotorwrench]

Pushing pressure into the tank is not the same as drawing fuel out of the tank. This certainly may not be your problem but it is not impossible for that to happen. Something as small as a plugged vent can stop fuel flow. Vented caps can be problematic at times.

If fuel flows to the carb good then check all the other stuff.

The previous poster has a point if the car has electric overdrive. There is a feature of the down shift system that cuts the coil off momentarily to hasten the down shift.