Everything else checked out, bad IP?

[Middlemancrisis]

Hey guys, is there a more definitive way to check and see if an IP is bad?
I have a '94 and a '96 GMC turbo diesel. Both electronic injection. The '94 runs great. The '96 starts for 1 second then dies. I bought it this way. I don't know the symptoms leading up to it's current non-running condition. When it fires for the 1 second it sounds as good as my other truck.

Here's the thing. I swapped out the lift pump, OPS, PMD from my running truck and still no go. It does the same thing, starts for 1 second then dies. I swapped out each one at a time and gave it ample time to prime the system.

My guess is that the lift pump is putting enough fuel to the IP to get it to fire over before it starves itself of fuel because the lift pump can't supply the pressure like the IP can.

There appear to be no fuel leaks. So what else can I do or check for?
Is there a way to bench test the IP while it's still on the truck to determine if it is just a bad IP?

Thanks guys

[JohnC]

Could it be running in the "start" position but not when you release the key to "run"? Could be an ignition switch problem. (Question: can a Diesel have an ignition switch?)

Otherwise, see if it has set any codes. The PCM may be shutting it down because of a perceived problem, especially with the electronic throttle control.