How much diesel you have in your tank? The tank has a sending with a pre-screen anything under 3/8 of a tank and some moving could cause the hunting or die.
I forgot to tell you this find some clear 3/8 line and some connector that fit the your lines and see if you have bubbles. You have to reprime the system and let it run for a bit somewhere 3 to 5 mins.
https://youtu.be/YJgbvwIuJjQ
Need to make sure first that you are not getting air in the system before you get the injector pump.
It drove me crazy trying to find it I still had the problem but it was random one day I could start and go np. Other days she did want to start and hunting. Till I was under the hood running I smelled diesel. I figured you would smell the exhaust not so much diesel fuel. I start going every line seen the injector pump was leaking from the wfs to the pump line. The rubber o-ring was bad from age.
The only cool thing of getting air in your lines when it's very little will give more power and better mpg but could hurt you injector pump.
The injector pump cools by diesel fuel.
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