The fault B1601 Code is related with the engine of the car and at the diagnosis time, the code appears. The fault code has dictionary meaning but based on the model and manufacturer, the meaning of the code changes. You can solve the problem if you have all machines and experience for solving the problem of the engine. After solving the problem of the engine, take the car for test drive. There are presently two key types of cylinder diffusion used today and depending on the kind of engine. The B1601 code for the pushrod design that uses solenoids to change the oil burden transported to the lifters.