'05 duramax loosing fuel pressure
 

have fuel issues with a `05 gmc 4500 duramax. truck looses prime and stalls at low rpm


Optional Information:
Make: GMC
Model: 4500
Year: 2005
Engine: duramax diesel

Already Tried:
r&r fuel tank and cleaned,new fule lines tank to engine, new cp3 pump assembly,replaced the check vale unit in filter houseing,new injectors (8),

did you rebuild the filter housing?

do you have a scan tool to monitor rail pressure??

We did rebuild the filter housing and the readings i got on the scanner are:
des frp (mpa) - 1235 {at 1200 rpm}
act frp (mpa) - 1220-1240 {at 1200 rpm}
des frp (ma) - 35 {at 1200 rpm}
act frp (ma) - 35 {at 1200 rpm}

Have you checked to make sure the water in fuel sensor is not cracked?

We replaced the water separator sensor with a new one

temporary install a section of clear fuel line on inlet an outlet of filter housing and check to see if you are getting air bubbles in fuel before or after housing.

well, we ran some more tests and come to find out, the brand new cp3 was defective! So we replaced that and now it works great, so thank you all for your help!!! its actually nice seeing this truck drive out of the driveway!! Thanks again!