I have a 1990 with a 5.7, the truck will bog and stumble at anything over about 10% throttle, so much so that I cannot get it to over 25 without it falling on its face and trying to die, it has not seen 30mph in 3 months now. Prior to this I went through 4 fuel pumps in 3 months about 2 miles of on road use combined. I have changed just about every sensor and relay that you can. Now for what I do know. With it in this current bogging state I have only 7 psi of fuel pressure at idle, it will jump to 12 psi very quickly right after it is started but once any gas is applied it drops to 0 and then returns to 7 when I let off but it will maintain the 7 psi for a while once it has been shut off. Yes the fuel tank is corroded I have a new tank on the way. I also know that the fuel pump only gets 8.4 volts with the truck off. Is the tank and the low voltage the reason for this issue and the burning of fuel pump or is there something I’m missing. If the low voltage is a cause, how do I fix it? Thanks in advance.