The engine trouble U1077 Code is important thing and it has varieties of meanings but an automobile engineer needs to use original meaning of the code what is linked with the car brand and model. The engine code U1077 seems a kind of network problem and this problem is not very difficult to solve. There are now 2 types of cylinder diffusion used and it depends on the sort of engine. The engine U1077 code for the pushrod style which uses solenoids to change the oil compression carried to the lifters. The lifters are powerless to lift their companion pushrods below the valve rocker arms, resultant in valves that cannot be activated and remain closed.