Koch Chemie Mehrzweckreiniger (literally translating as multi-purpose cleaner) is specifically an interior and specialist cleaner for deep and thorough removal of oil, grease, soot, smoking discolouration, and ink. It is made for use on plastics, upholstery, roof linings and fabrics. It has an excellent ability to dissolve dirt and remove it and will leave a nice fragrance behind after use. The product has received Daimler approval in Germany.
Depending on how bad the dirt is to be cleaned, the product can be diluted 1:5 or up to 1:50 through a spray bottle or direct onto a microfibre mitt. Once applied, it should be allowed to react and then worked with a brush or cloth and any excess wiped off using a damp cloth.
Can also be vacuumed up with a wet & dry vacuum cleaner or used in conjunction with a carpet upholstery cleaner but if putting in a machine it is recommended to use a defoaming agent such as Koch Chemie Kocentschäumer.