i live in vermont and my duramax wont start in the morning once u get it started runs all day even when u shut it off and start it a thousand times almost like it looses fuel pressure over night but the primer is solid after around 3 pumps any ideas

 

but does it start after you prime it?

will it start quickly while still cold in the morning after getting it started? get it started, shut it off and restart it right after

still sounds like an air leak/priming issue to me though

 

it won't start by pumping the primer up only if u start it with starting fluid but now that its warming up around 20 to 30 degrees it just starts hard im throwing a p0380 code and i think i narrowed it down to 2 bad glow plugs and it is cali emissions let me know if i could be wrong

 

mine starts just fine with out glow plugs (have them disconnected) even in temps below 20 degrees. if you are getting fuel into the cylinders but it is not lighting off then you would likely have white smoke/mist coming out of the exhaust indicating unburned fuel.

do you have any way of monitoring the fuel pressure while cranking? fuel pressure needs to reach at least 1450 PSI (10 mpa) before the ECM will open the injectors.

you could always replace the glow plugs and see if it fixes the problem, but i have my doubs

 

Got it started this morning no white smoke and then shut it off and started but still started pretty hard still no white smoke wouldn't start with pumping the primer hard? Any idea hope this helps

 

found my problem had sand in injectors on other side changed them starts very fas i changed the drivers side last year had sand in three of those too starting to get mad

 

are you referring to this: http://merchant-automotive.com/tech/lb7line.pdf

if yes, then it is likely you just had some bad injectors and since you changed out the driver side already these where next ones to go

if not and you actually mean sand as in beach sand/silicon dioxide/SiO2/etc, then it is time for a fuel line flush and finding the source of this sand as it is not a normal part of the fuel or fuel system

 

Yes it was sand grain

 

so the questions now are:

how did the sand get in?

how did it get past the fuel filter?

and how did it get past the fuel pump?

might be worth pulling the bed and looking into the tank to see if there is any sand in there.

perhaps a sabotage?