Engine shutsoff safety feature?
 

Hello,
I have a 95S10 that I have transplanted a 98 S10 2.2L engine with standard trans, wiring harness and ECM from donar too. This is what I have, 46PSI fuel pressure, drops to 38-40 PSI on start up, engine fires up runs for about two seconds and shuts down. Fuel pressure is steady, and holds. Is there a safety feature on the 98 for oil pressure or anything else? Meaning if ECM doesn't receive input to kill ingnition to save the engine? Or am I overlooking something else?

Any suggestions appriciated.

How long has it been since that thing had a new fuel filter? You should be running more around 60psi. How old is the fuel pump... could be a partially clogged fuel pick up screen?.

New fuel filter, don't know about the fuel pump, worked fine on previous engine until head cracked. Also, when engine starts, it run as previously mentioned, but will not start back up, you rotate key to off position then back on and engine fire right up for a few sec then shut off. Fuel press is steady, not much of a drop off from starting to running to shut down.
How accurate is a Chilton Manual? Its showing I should be running 41 to 47 PSI with Key on with a MFI system, 98 is a SFI system, no listing for SFI so I'm assuming MFI information but you guys know what assuming does. Are these pressures correct? Or should it be running pressures 58 to 64 for CMFI system or 55 to 61 PSI per CSEFI?
The reason I think its electrical is due to the turning the key off resets something in the system to allow for ignition but shuts down after a few sec due a safety feature. Still troubleshooting the problem, suggestions are welcomed.

What size was the 95 motor you took out? Could it be that you aren't providing enough fuel pressure to the new engine for it to run? I have seen just a couple of fuel psi make a vehicle not run/start.

Any check engine lights?

original engine was the 2.2L MFI system, no check engine lights either,

Sounds like the passlock system. The 98 has a passlock sensor in the key barrel to prevent theft. The 95 has no such theft deterrent.

The passlock is wired into the BCM, then the BCM sends a signal over the data line to the PCM to allow the injectors to fire.
You need to get the BCM from the other truck, the wiring harnesses, and the ignition barrel