05 duramax 2500 hd 4x4 crewcab shortbed.Pulling my toy box trailer going up a long hill I saw a big puff of black smoke out exhaust & check engine lightcame on & I loss power. limped to our camping spot & turned it off. A couple hours later I started it up& the light was off & it ran fine. Took it for a test drive & the 3rd time I got on it hard it did the same thing. took it to a gmc dealer,(not a chev. dealer) & they said it was a plugged fuel filter so they put a new one in & On the way back to camp got on it to make sure that was it & the 3rd time it did the exact same thing so i called chev & they sent a tow truck & took it back to them. They called & said it looks like a "Leak in the tank" Still waiting to hear from them & I,m 300 miles from home. PLEASE HELP me diagnos this Thanks Rick

SOURCE: Chevrolet 2500 Not Running, May Be Fuel Filter Sensor

That red wire is only for the fuel heater.will not cause a no start.try pumping the primer pump on top of the fuel flter hsg. but first open the bleed screw,which is black plastic also located on the top.this will eliminate any trapped air that might have entered the fuel intake system.if the pump does not get firmer and harder to push, then you have a leak in the fuel supply lines or the ck valves in the fuel filter hsg or stuck open. Still no start have it scanned to ck fuel pressure while cranking.it should be close to 5000 lbs

SOURCE: engine looses power going up hill, no check engine light at this time.

How old is the Catalytic Converter, sometimes they will get clogged up and affect performance.
Good luck

SOURCE: Chevrolet 2500 Not Running, May Be Fuel Filter Sensor

if it dont have good compression it will not start check the comp and make sure there no water in oil if fuel pressure is low it will not pop the injector open try some starting fluid

SOURCE: suburban low pressure from fuel pump

Try checking the fuel filter and then the pressure regulator on the rail. If the pressure regulator is bad it will not let the pump push enough pressure. And if the filter is clogged then it will also not let the engine get enought pressure. I have seen pumps starter going out by losing pressure. I have also seen aftermarket pumps quit after about a week unles you did not change the whole assembly.

Testimonial: "Thanks! I was unaware of the regulator. We did check the filter. Great info!"

SOURCE: 2007 chevy silverado 2500 hd duramax shut down

mo me it sounds like low fuel volume i would check my lift pump