The engine U1103 Code is very helpful and if you do not find the real meaning of the code, you cannot solve the car engine problem. The engine code is a kind of network problem related code of the car engine. Do not use false meaning for fixing the car engine problem. However, the valves of separate cylinder are reserved closed using a pair of arms what swap the conservative engine’s roller-type rocker arm. The engine U1103 code is one of these arms what follows the cam profile while the 2nd arm connects to the valves. During usual engine process the two arms are linked by a locking pin.