My truck is a diesel and has about 100,000 miles on it. The starting issue was very intermittent at first, but now the truck will not even start. Seems like a fuel issue to me. When it does try to start it is only after I feather the fuel pedal or prime the fuel filter. There is fuel in the tank and though it has been below freezing the last week I can be almost certain the fuel is not frozen or waxed. I use an additive that eliminates water and protects the fuel otherwise. I have not tried to bleed the air out, if there is any. I am looking for a place to start diagnosing?? I am not sure how to check lift pump or injector pump, so any help with fuel delivery issues would be greatly appreciated!