FAST fuel issue

[No Quarter]

I'm not certain but I believe the FAST contorls pump voltage somehow.

Here is my continuing problem. I have normal FP when driving. However as the car enters boost it dies off. As soon as boost is present FP drops to 20psi. I have a weldon 1250 pump. Capable of more than meeting my systems fuel needs. The vaccum line slipped off the FP reg a few days ago but now reconnected does the exact same thing as when it was off. ie - does not increase FP as boost rises.

Is it possible that I have a poor vaccum signal? Should'nt be as it adjusts FP while in vacc - the pumps voltage is adjusted by the fast is it not?

I'm at a loss.

 

[T66Typhoon]

The fast does not control the fuel pump voltage at all. All it does it turn it on and off.

Could be you have a bad fuel pressure regulator.

One other guess that is WAY out there is that your feed line is not sufficient for delivering the volume of fuel that you are trying to deliver... that is way out there, but I don't know your set up.

 

[Chuck Leeper]

1250??

Just went thru my WELDON catalog.. don't see a 1250 listed..
You don't show any info on the application such as the car, the engine, etc.
Is this a BUICK??
What kind of regulator do you have? What do you have the pressure set to?
We need more info B4 we can make suggestions.

 

[TurboJim]

Maybe 2015? If so, this is the second instance of this problem I heard in the last week