Pressure control valve

[Joush]

I believe the PCV is sticking in my hpfp but not sure if thats whats going on. When I accelerate and the motor starts to get a load on it the rail pressure drops to 1300-2000 psi for a few seconds then shoot up (I've watched it go as high as 29k), driving around pressures are are normal with no fluctuations. As the rail pressure drops the PCV is rising up to 50ish % and when pressure comes back the numbers drop to normal for the desired RP. At idle or off throttle the rail pressure will read a couple thousand psi above desired until I restart the truck then it returns to normal idle pressures.

Anyone have any experiences with this? I already ordered a pump and install kit being the truck has 320K on and supposedly all original.

 

[Joush]

Also pressure at the cooler holds 5-6 psi when I brake boost it.

 

[Jonnydime]

Every time this has been brought up on this site it has been because of a bad ecm

 

[Joush]

That was one of my thoughts too. I played around with it today trying to rule out any wiring issues and the cover harness resistance for the solenoids is pretty high (38 mohm). When the new pump and harness come in I'll double check the resistance on them to see if they are any different.