"Tune up" is a term that is commonly used by car enthusiasts and mechanics alike, referring to the maintenance work needed to keep a vehicle's engine running smoothly. However, there are other words that can be used as synonyms for "tune up". These include "maintenance", "repair", "overhaul", "service", and "check-up". Each of these words can be used to describe the process of inspecting and fixing various components of a vehicle's engine, such as the spark plugs, air filters, and fuel injectors. Whether you're an auto technician or just a car owner looking to keep your vehicle in top condition, it's important to understand the different words that can be used to describe these important maintenance tasks.