Direct injection fuel injectors require the fuel injector decoupler – 13537564751 is replaced at the same time to ensure the fuel injector is seated properly. Failure to install a new decoupler or reinstalling the fuel injector without a decoupler will cause ovaling of the fuel injector hole in the cylinder head. The fuel injector comes with the o-ring.
This part is a supersession to BMW OE Part Number 13537585261. These new fuel injectors have a new calibration to improve performance and reliability and therefore are indexed as -11 and up. They cannot be mixed with fuel injectors which are indexed as -10 or below. If your vehicle has index -10 or below then all of the fuel injectors will require replacement. A fuel injector is actually a combination of a nozzle and valve that controls the delivery of fuel into the combustion chamber of an engine. The nozzle is carefully designed to atomize fuel in a very fine spray to achieve a homogenous mixture of air and fuel. A failing or clogged injector can cause incomplete burn and/or a dangerous lean condition in a cylinder. This can present itself as a misfire, hesitation, stumbling, or low power. Leaking fuel injectors can have symptoms such as hard starting, poor emissions, increased fuel consumption, damaged catalytic converters, and increase fuel odor in and around the car. Some success can be had with fuel injector cleaner but it is critical to an engine’s performance and life that properly functioning fuel injectors be used at all times.
