P0251 Injection Pump Fuel Metering Control A
P0252 Injection Pump Fuel Metering Control A Range/Performance

All in the pump, sorry to tell you.

Look at this though, could be a lifesaver for him:
https://www.dieselbombers.com/sale/57387-vp44.html

Thanks RA I tried swapping the realys too and still the same but I will check on that pump thats will work for sure for him thank you for the imput

your going threw a lot of work for nothing , scan the codes

if you can get it to autozone or advanced auto they will scan it for free

I was able to scan it for codes found a scanner i was able to borrow and found two codes that kept coming back. P0251 Injection Pump Fuel Metering Control A,
P0252 Injection Pump Fuel Metering Control A Range/Performance. So im thinking time for a new VP :dang:

$$ - a FP guage is essential - especially if he has an oem lift pump. Make sure he buys a pump that has new electronics on it.