When it comes to routine maintenance, changing your oil is one of the more inexpensive services. Despite its relatively low cost, oil plays a vital, multifaceted role in your engine, and spending a little money on routine oil changes can help prevent you from forking over large sums of cash down the road. Engine oil provides three key functions in a modern internal combustion engine. First of all, it helps keep engine components working smoothly together. Secondly, the inside of an engine, a place where there are thousands of controlled detonations happening every minute, can be a hot place, and oil helps draw heat away from the combustion chamber. Lastly, it helps prevent carbon and varnishes from accumulating in the engine.