The B2501 Code is an important thing for solving the car engine problem. The code B2501 OBD2 exactly mentions to the camshaft (cam) timing. For this case, if the cam timing is over slow, the engine light will be illuminated and the code will be fixed. There are 2 types of cylinder deactivation ways used and it depends on the sort of engine. The engine B2501 code for the pushrod style and it uses solenoids to alter the oil compression brought to the lifters. In the distorted state, the lifters are impotent to elevate their companion pushrods under the valve rocker arms, ensuing in valves that cannot be started and closed.