Suburban 99 just die

[rcobar]

I was running on the freeway (65 mph) then my 99 Sub just die.
I had check all the fuses, the fuel pump relay and everything seems to be ok. The fuel pump make the working noise when I turn the key to the On position. I had changed the fuel pump today to see if there is a problem on it but still not starting. But when I put some starting fluid on the intake (is the 5.7 vortex) the engine starts and works for couple seconds.
Where could be the problem?

[zirb]

See if you got fuel pressure at the test port. It is on top of the intake by the firewall. You should have 50-60 psi. Fuel filter?

[BURBAN18]

It may be the theft deterrent system, we had similar problem on our 99 Tahoe.