This aftermarket component set is designed for specific diesel-powered vehicles manufactured by BMW in 2011, specifically the 335d model. Its primary function is to remove or bypass certain emissions control devices originally installed by the manufacturer. An example of a component often targeted is the Diesel Particulate Filter (DPF).
The appeal of such a modification often stems from perceived improvements in vehicle performance and fuel economy. Some owners believe that these systems restrict engine output and increase maintenance costs due to potential clogging or malfunctions. Historically, modifications of this nature have become more prevalent as vehicles age and emission control systems become more prone to failure, leading to expensive repairs.