ok so i got a 01 lb7 with a zf6 tranny that runs fine once started but when it comes to starting is a she-devil! sometimes it'll only crank 10seconds or no start. mostly it starts but more often i have to crank for 30 plus seconds. it seems to help by holding the petal to the floor PLEASE HELP IF YOU CAN

 

check your oil and see if you have any diesel in it.
and then check your battery cables for corrosion then check your fuel filter housing and see if you see any fuel leaking from the plunger on the top

 

i've checked the oil and all is it should be. i put an after market fuel pump thinking that would solve the issue, nope. the batteries are good, red top otimas with a good connection. i've cleaned and checked all the lower engine grounds. all the wiring connectors have just enough electrical grease. i replaced the cp3 and the ficm so i cleaned and greased all the connectors to get the truck running!! in has brand new heads on it. oh when it finally decides to fire the injectors its a poof of white followed by strong black. it doesn't haze if i leave it idle for long periods of time so it makes me question if its the injectors

 

Pull the injector fuse and then remove all the glow plugs and crank the engine over while having somebody watch the holes where the glow plugs were. It sounds like you have an injector hanging up and if that were the case then you would have a no start completely which you almost have and you would see fuel spraying out the glow plug hole.

Do you have a way to monitor rail pressure?

 

no. how would i test the pressure

 

Using a scan tool like efi live or a tech 2.

 

ok well i have a friend who knows someone that'l scan it free and diagnose and fix or tell mehow pretty cheap overall, a case of guinness

 

 

ok so we think its the cp3. i replaced i in december so im warrentying it out. it was only getting 800 psi crank pressures

 

Sounds like it