P0087

[integritymechanicsbydavid]

Just finished 500 mile break in on fresh KKD steel piston long block. KC Stage 2 low pressure turbo, 25 over injectors, running a break in tune. New AirDog 2 5G lift pump with RCD fuel bowl delete regulated return.
I’ve have several issues maintaining the same pressure at the return gauge.
While driving at 60 mph I felt a little slow down and looked at my Mini Maxx V1 and noticed the FRP had dropped to 1.8. Then I hit the throttle and it went back up to 10.7.
I pulled over and checked the gauge at the return and it was down at 3psi. I turned it up to 7.5psi and cleared the code and drove some more. It happened again and I pulled over. I readjusted the pressures at both the regulator and pump to read 8psi at the gauge. Drove another 115 miles without issue and then it dropped to 1.8 and spiked up to 22.5 all within a second.
Anyone have any ideas? The HPFP was replaced under a year ago. The HPFP gasket is motorcraft as well as the sensor but not the injector harness.
I have injector knock at low RPMS but not idle and my tuner said it’s normal.
I haven’t been able to catch and abnormalities with my Autel watching live data.
Any help is appreciated.

 

[DEEZUZ]

Im basically at a point to say that there are no good reman 6.4 hpfps. I've put 2 or 3 in before I got a good one. Same issue as described.

Some of them I was in there resealing the motor and up sold a hpfp just because we were there, only to end up putting their pump back in by the truck had an issue after a new hpfp was installed.

 

[integritymechanicsbydavid]

I don’t even understand how a company can charge $1,000 for the reman pump and it fail unless the valves they’re using are Chinese.

 

[DEEZUZ]

I believe these pumps nor solenoids can be tested via a bench. And I don't think they re making new OEM quality valves. COVID we were getting them with loose vcv and pcvs...

In a few years all the 6.4s will be gone and swapped. Nobody wants to work on these and I don't blame them. Even I'm starting to turn them away due to untrustworthy parts and support.

 

[DEEZUZ]

There was one place advertising brand new OEM pumps but my company wouldn't buy them. So instead I'll throw junk pumps in and warranty them over and over. I'm hourly, so I don't care.

 

[integritymechanicsbydavid]

I just put $45,000 into this truck without labor cost and the pressure control valve started acting up. It hasn’t even made it to the high power tune yet. And now I’ve got to jump through hoops for a warranty replacement and buy the replacement pump and wait for “testing” to confirm the issue before refund.
Definitely not happy.

 

[DEEZUZ]

Yup.

Been there.