Here for sale is a used A4 Genuine Mercedes OM651 2.1 Diesel Introduction into Service Manual. This engine is fitted to many Mercedes C & E class models from around 2011 onwards. This manual was produced in 2008. This is a 57 page manual explaining the construction and operation of this engine with lots of useful information. It has been used but is very clean and complete. Buyer welcome to collect or happy to post.