I had a similar problem.
The solution was:
Take injectors out and have them cleaned and tested. Mine needed cleaning and one new injector tip
Took both lift pumps out -- NOTE -- Take 'em out one at a time, and always leave at least one pump installed....
My injector pumps would not rotate. I took each pump apart; removed the piston, then polished the pump piston and pump 'cylinder' with some chrome polish.
Re-assembled them and the engine started. The first time it started I had to crank it a bit, but from then on it started like my old '54 cj3b jeep -- two revolutions and it's running.
Take the pump apart carefully. First thing is the upper portion which just unscrews. Some parts are likely to fall out of the unit, so note the order in which they come out. That part is intuitive.. If, as in my case, no parts fell out, all that means is that they, too are stuck and you'll need to remove them and clean 'em --- I used lacquer thinner.
If you stand the pump vertical and look at the side of the pump the external pin that goes into the rail will most likely be stuck in the far left position...
Next, with the pump stuck in the far left position, look down into the pump and note the notch on the piston. Also note the relationship between the notch and the port where the fuel enters. Once disassembled, it is possible to assemble the pump 180 degrees out, but if it is assembled 180 out the relationship between the notch and the port will not be the same as original with the pin to the left. It is really quite simple, and once you've finished the first pump you'll feel like an expert when doing the second one.
The way the piston is held in the pump is by "forming" the bottom edge/lip of the housing so as to prevent it from coming completely out of the housing. So when removing the piston, "form" the housing so that the piston can be removed, and "re-form" it after re-installing the piston in the pump.
The ONLY difference between "forming" and bending, is that when one "forms" he knows what he is doing, and when one "bends" he doesn't.
When re-assembling, I made use of an old wooden chopstick as a tool for holding the piston in place when installing springs.
As a side benefit, since the chopstick had been modified to use as a tool, I "just had" to go back and get some Mongolian Beef at the local Chinese restaurant ---