How do I check if my Audi A4 has a knock sensor?

I've heard that knock sensors can cause issues in Audi A4s, but I'm not sure if my car even has one. How can I check for a knock sensor in my Audi A4?

A simple way to check for a knock sensor in your Audi A4 is to look up your vehicle's engine identification code and cross reference it with a list of known knock sensor locations. This can usually be found in your car's owner's manual or by doing a quick internet search. If your engine code is listed as having a knock sensor, it's safe to assume your car has one.