Cummins Lift Pump Issues / Airdog Install!

Noticed my lift pump wasn't making any noise the other day. Went to test fuel pressure and had 0psi! Thats why a fuel pressure gauge is a must in these trucks. Truck ran and started perfect which was the strange part. Installed a birddog raptor direct replacement and did some custom fuel line mods to it. Please subscribe for more content! And comment with any questions!

[@DrivenDiesel]

Good stuff I’ll test mine out

[@enginesadventures5689]

Better safe then sorry!

[@michaelloth5870]

I unplugged the connector from the pump and connected my volt meter to the wire harness. I get 9 volts initially. Once I bump the starter I get 12 volts for 20 seconds or so. The 9 volts seems odd to me and it is very repeatable so I think it is normal, but not 100% sure? Why put 9V on a 12V pump? It might be that the VP44 Injection pump does not want to much fuel pressure at start up?

[@Reviewerguy1228]

I installed airdog 2 4G and now I’m throwing code P1689 and truck will not crank/ start

[@enginesadventures5689]

I’d check for air in fuel

[@ixryq8368]

I got same code but it’ll crank and start but not go over 1400 rpm. You fixed your problem?

[@ryanslattery2977]

Any update?