The DF-165 has an adjustable regulator built into the side of the pump
. I used a gauge to dial it to 12psi. Factory, the pump was at 16psi and after reading I dialed it back to 12psi to be safe. At WOT, it dropped .5psi, so I know I'm safe there.
The code that said "Metering Block Malfunction" was probably due to excess fuel pressure that it could not get rid of. Honestly, I paniced at first. The instructions that I got via phone AND written were all jacked up. I was told that the DF-165 recycles the fuel IN THE PUMP
and that there was no need for a return line to the tank.
This (I now know) was absolutely the wrong thing to do and after 5 gallons of wasted diesel on the shop floor, everything was ok.
After all that, I drove it for 20mins, went to fill up the tank, and after restarting the idiot lights went off. So far I've drven it 400 miles with no issues, other than a leak (hemorage) of diesel from a fitting. That is the only bug that I had to work on. I looked at it this wat though, as much fuel covered the underside, I won't have to worry about road salt or chemicals eating it this winter. =)