In our tune we command almost 15 volts to the pump because it is barely hanging on at the stock voltage of 12.xx. It’s a smart move to upgrade the pump in almost anything but a stock application. It’s true that the injectors and HPFP are usually the first upgrade on our fuel system but the in tank pump is being “heavily managed” in tunes to ensure enough headroom. Yes it is likely he would need a tune revision to make the pump play nicely with the other components but I’m sure he already knows that.
Unless you're full throttle 100% of the time I can promise you that fuel pump does just fine. Also I doubt it sees 15 volts all the time especially since the Ranger comes with a variable voltage system and does not run at 14.7 all the time.
How can you promise what is in a custom tune in my truck? The voltage is of course variable. It is commanded based on load etc. in the tune the alternator is commanded to charge at higher voltage thus allowing the FPDM to be commanded higher as well. Adding a higher performance pump would allow us to reduce those voltages back down some so it wouldn’t be such a demand on the charging system at wot. Understand better now?
Unless your tune has specifically disabled the variable voltage system there is no way it is putting out that much voltage. How can you confirm this? If you have the gauges to run it simply have one of your data points on display be battery voltage. If your battery voltage shows it will let you know what the entire system voltage is and with the maximum voltage to your fuel pump will be at that time. You will be amazed on how much voltage will not increase magically after the PCM when you're alternators only putting out so much.
What do you think aftermarket tuning does? It’s adjustable in the tune just like hundreds of other parameters.
Like said unless they disabled the variable voltage system then it's not running that high of a voltage all the time. There's an easy way for you to check and I can promise you most likely your custom tune did not disable it
