Quote Originally Posted by Stazi View Post
Seems unlikely as he says the Fuel Pump is running and is getting 9psi (which seems high). I'm thinking you have a stuck float that is not allowing fuel to refill the bowl quick enough, so the 90 seconds it's running is the time it's taking to empty whats in the bowl after it has time to slowly refill. This would suggest why you're seeing the gas pressure on the high end; restriction INTO the carb.
Take the fuel rail of the car and check to make sure it's not blocked and then remove the bowls and check the floats and the vales in there for gum and dirt blocking it up.
Forgot to include the original reply from Stasi.

True, but how long is the fuel pump running? It could be running until the pressure switch takes it out. I would not rule out a faulty oil pressure switch. Check the oil pressure gauge while idling and see what it does when you throttle up and see if it drops. All of the symptoms sound the same as mine did and turned out to be the pressure switch. The pressure switch is not expensive and easy to change.