whats wrong with my truck
 

i just got a 96 dodge cummins. i had two things happen today. first i started the truck, and after a few seconds it shut off. but started right back up. then i went to shut it off after driving it, it stayed running after i turned the key off. i noticed after that that i have fairly good fuel leak from the rubber hose part of the return line. if i replace that line is that gonna fix my problems. or is it something else

fuel shut off solonoid is going bad......need a new one bro

check this first

Diesel Hard Start Diagnosis

X2 I would check that first