[yo2001]

Okay, I got a question. my car some times shut off the fuel pump when I get off the throttle. I thought through the problem and it must be the AFM is shutting close and cutting the fuel pump off. Is there a solution to this? Nothing else wrong with the AFM.

 

[TurboSi]

Once again, what kind of car, what year? How do you know the pump itself is being cut off? Do you have a fuel pressure gauge in the line to verify this or, perhaps, can't hear it when you close the throttle? Or do you mean that the fuel supply via the injectors is being discontinued? More information, please.

 

[Zuber]

If you have a 77 or earlier FI 280, then the following applies.

If your fuel pump safety circuit (contact riding on the flap of the AFM) is incorrectly set, then it is possible that the fuel pump could briefly shut off during running.

I had a problem where the rpms would drop below idle when I got off the throttle. Sometimes it would drop below 500 and die.

I found that the contact in the AFM would break even though the flap was open. I slightly bent the contact arm so that the circuit still worked, but would only break if there was NO air movement through the flap.

I still have the idle issue, but it no longer stalls. YMMV.