My 1990 5.0 will start just fine then 2 seconds later die. Any ideas.

 

Welcome to the site!

Suggest throwing a pressure gauge on the fuel rail, ensuring pressure stays up in the 35-40psi range.

A bit further out there is the idle air control (IAC) solenoid, ensuring it can move freely.

The more details you can provide, the better we can help. Such as feathering the gas pedal changes anything, hearing the 2-second fuel pump prime when the key is rolled to On, etc.

 

Thank you for the welcome
I hear the pump I'm doing the fuel pressure tomorrow and when it's about to die I floored it and almost killed it then let off and did that about 6 times then it ran fine

 

I have figured out the problem my fuel pump strainer was in a million pieces so it wasn't getting enough fuel