Its funny you said this as I remember in 1992 when Mopar went to a returnless EFI system and thats about when I started seeing the fuel filters on the Caravans mounted by the tank with a third line that was a return to the tank. And of course it had no return line of regulator up front. Mopar told us that the PCM was now smart enough and worked fast enough that when you stepped on the gas pedal fast the PCM could increase the pulse width fast enough that it did not need the higher fuel pressure anymore that the vacum controlled press regulator gave it when manifold vacum dropped. At that time they did put the fuel pump on its own relay but it still fed the pump a solid 12 volts through its relay and it's relay shared its ground at the PCM with the shutdown relay so it did not pulse width the pump to change its speed or pressure. I remember in training at that time in 1992 when Mopar first used the returnless system and eliminated the vacum fed press regulator they just told us that the PCM worked fast enough that it did not need the vacum fed pres regulator as the PCM could increase inj pulse width fastenough to handle it. Ron