Ford's answers to the NHTSA 6.7 Investigation

BenK wrote:
snip...
The metering valve seems to have a piezo, but wouldn't a plain spring
loaded one way work? What are they metering for? Do they allow back
flow as the metering method? then slam that metering valve shut to
then allow the cylinder to raise and open the one way to the common
rail?

Wonder if any association with the timing of this pump with the injectors
and that they don't have a large enough accumulator?

Nope, failure mode is not good and the more I noodle this, the more
confusing it looks on what is really going on

If they did pitch off the cylinder chamber on the intake stroke, then
the chamber goes negative to stop the piston from going all the way
down...would the cam then slam into it on the compression stroke?

Can kinda sorta see how that might work, as the piston isn't fixed to
the follower. Once pinched off, the piston will NOT continue down
with the follower, but then does the follower slam into it on the up,
compression stroke?

Then that 3rd tiny port with a restriction by reduced dia...what is it
for?

Can see how the return to tank port inside the exhaust port works, but
that 3rd port?? Balance in some way as it does feed into the relief
valve spring cavity