It's hard to tell whats going on with just the info provided but I would try changing the fuel filter if it hasn't been done in a while and see if that helps. That can significantly reduce power when it gets old.
changing power steering hoses on 2007 sierra duramax
The 7.2 liter is a Duramax diesel.
Yes, there are wiring diagram available for a 2007 Chevy 2500 Duramax. These are available in the cars maintenance manual.
The radiator diagram for a 2007 Duramax can be found in the maintenance manual. A radiator diagram can also be obtained by asking for a printout at an auto part store.
The 2007 Duramax has to different models offering different horespower. One model offers 300 horespower, while the other model offers 330 horespower.
Your injectors are failing Also, could be the turbo seeping oil past the bearings.
13500
They are underneith the valve covers.
(Lb7)300hp (LLY)310hp and 320 hp on LLY models put in 2006-2007 trucks (LBZ)360hp (LMM)365hp
9.5
On a 2007 Ford F-250 : The power distribution box is in the engine compartment ( on the drivers side of the engine compartment , near the firewall )
Remove the fuel filter, fill it with fuel... IIRC, the Duramax has an electric fuel pump... cycle the key in the "on" position a couple times to let it prime.This is, of course, assuming that, when you say "gas", you actually mean #2 Ultra Low Sulphur Diesel, which is the only fuel you should be using for that engine, especially if it's 2007 or newer.If you ran that diesel engine on gas you probably destroyed the engine. That's why it won't start.