2006 5.9 Cummins everything stock 230k will crank and almost hit sometime never starts. Unplugged grid heater shot some ether motor will run on ether for 3sec then shuts down. Lift pump is good did a flow test. Blocked off injectors 1 at a time no different, could not figure out how to disconect the return line that comes from the back of the head to see how much fuel is being rerurned so i cut the hard plastic line at the aluminum hard line. While cranking I got prob 500ml of diesel return. Sounds like injectors or bad, I agree. Now I do have a question about the return line, the side from the tank would also flow diesel fluid while cranking. I did another lift pump lest to be sure I didnt take off the wrong line. Lift pump still good. Oh also checked the pressure relief valve on the common rail it is also good. So do Yall agree its injectors before I spend $2.5k? And why does the tank side return line have fuel flow whike cranking? Thanks and happy resurrection day God bless ye

 

Hello if you have high injector return flow I would try to retorq the connector tubes

 

What is your cranking rail pressure? Takes 3k to start

 

Update.. Replaced all 6 injectors with Bosch remans, truck now starts and runs great but blows white smoke slightly(cold) after a few minutes of running it blows white smoke excessively (warm). It deffientaly smells like fuel, i capped one injector at a time truck started right up with no changes in smoke. Replaced fuel filter. Drained my tank and put in fresh fuel. Added seafoam. Any ideas? I also checked the blow by zero pressure coming from oil cap, very little smoke/vapor.