Starts and runs for 3 seconds

I'll get a guage and check it tomorrow. I did check the spark plugs today (they are new ) - black soot on all of them, one of them was gaped too small - reset the gap on all of them. Now the engine will run for exactly 4 seconds. Before regaping the plugs it would run for exactly 3 seconds. Took off the fuel rail with all four injectors - they all have a very nice spray. Bypassed fuel relay to keep the pump running - engine still dies at 4 seconds. Will check pressure next.

Checked fuel pressure today. Pressure coming out of the pump: 75psi, pressure at the rail is 49 or 50psi - with or with out the vacuum hose plugged into the manifold port.

Ok, so the regulator should be keeping the pressure at 37. I'll try and find a new one on Monday. As I understand this, the fuel pressure is too high at the injectors and they are spraying too much fuel into the manifold making the sensors send crazy signals to the computer - then the computer is shutting everything down? And all this stuff takes exactly 3 seconds? (I did get it up to 4 seconds - but now it is back at 3).

Installed new regulator yesterday, pressure at the rail was 43psi - engine would not start. Re-installed original regulator, pressure: 50psi - engine will not start.
It has spark, and it sounds like it will run, but when let the key off of the start position - engine stops.

Did start today, ran for 3 seconds, one or two times it ran for 4 seconds. Will only actualy start and run 1 in 6 tries.
Checked the wires to the shut off switch:

Pink/Black is 12v with Key ON
Orange has 12v also with the Key On - voltage stays at 12 while the engine is running for 3 seconds - and stays at 12v while/and after the engine dies.
White has.10 with Key ON and 1.5-3v when it does run.
Black is Ground at all times.

Was just thinking, what are the odds that the new crank sensor is a bad one?

What numbers should I be looking for?

If I put the Red lead from my volt meter to the Black wire on the cranksensor. And the Black lead from my meter on the Blue wire from the sensor I have a resistance of 6.88.
There is NO continuity to the Red wire on the sensor, and NO continuity between the Blue and Black wires on the sensor if I reverse the leads from the meter.

Can't find specs anywhere? Maybe they are not ment to be tested? - Only replaced?
I ordered a new computer for the car, it should be here tomorrow. We'll see if that fixes anything.

Just got the new computer today. I installed it in the car but it didn't fix anything. The engine still does exactly the same thing. I'm going to replace the crank sensor again, maybe that other one is a bad one out of the box.

Hi!
Airflow meter was my first guess also, back when I first started playing with this thing. If I remember correctly, if I unpluged the electrical connector on the sensor, the engine would not even start. If I left the electric connector attached but took the whole assembly off of the rubber intake hose, it would start but still only run for the 3 seconds. I did check voltages going to the connector - and I concluded that was not the problem, and started looking somewhere else.
MAP sensor - that is one that I have not checked yet. Do you know the procedure?
I have concluded that the Fuel pressure regulator is bad - 50 psi at the rail, with the pump running, vacuum attached or not - pressure drops to 5psi as soon as the fuel pump stops. Will also replace the fuel rail - the center part where the small o ring seats is not round and it lookd that might be the reason for the pressure drop.
Also found that one of the coils is arking to the valve cover - under the boot - as it sits on top of the plug.
Was thinking that maybe the arking coil is tripping the missfire sensor and shutting the whole thing off?

So today I just got my order from the dealer (to the tune of $575 ). I got a fuel rail, a fuel regulator, both coils and wires, ignition sensor, and MAP sensor. I installed it all on the engine and started it up. Guess what. Nothing new - it ran for exactly 3 seconds and died!

Was looking at the intake manifold - can't see exactly, but it almost looks like there is NO gasket between the intake manifold and the head? Seems to me that there should be one?