Want to check fuel pressure but sometimes the engine will only run for like 2 seconds. Can you get a usable reading just from the fuel pump priming when the ignition is turned to the "on" position?

Also, an off topic question for manual transmissions. Will you cause damage by moving the shifter through the gears when the engine is off?

 

Yes, you can. Hook up a fuel pressure gauge and crank it over. You can always jump the relay to run the pump without having to crank the engine. It may actually be helpful because you can listen to the pump without other noises present.

As for shifting the transmission as you describe, you won't do any damage.

 

what he said.

 

Initial fuel pressure will be about 35psi. When you start the car it will drop a bit but maintain pressure. Building initial pressure is not the test you really want. You want to know whats there when the engine is running. If you shutting off after 2 seconds I would look at your fuel pump relay in outside fuse box(inside the box).