yeah codes can be stored w/out a cel/ses or mil light.
california (CARB) based trucks will turn the light on (in some instances)
when other trucks wont (egr valve for instance)
GPR should not keep you from starting... You been cranking on it a bit? If your batterys are down even a little it will not start... Getting fuel? Turn the key on an listen for the fuel pump... If you hear it then open the hood and pop the fuel drain valve for a sec and see how much fuel comes out.