When VW released it's very first car, the easily recognizable VW Beetle or the Type 1 in 1938, few would've foreseen the design, much less cars produced and released at that time, to survive up until the present. Even with VW releasing a retro car based on the Type 1, the cult following and continued production (up until 2003) is evidence not only on the car's iconic status, but also reference to VW's engineering prowess.

VW has then proceeded to release other platforms with varying degrees of success, yet the reputation built upon by VW's first endeavor seems to follow the company's current forays to the ever-expanding automotive market. Outside of the oft brandished German ingenuity, VW parts are a product of properly configured engine and support applications that, with proper maintenance, allow for peak performance and durability of the vehicle. From filtration of air and oil as well as regulation of the temperature all play an important role in maintaining control of the mechanical chaos that is the internal combustion engine.

While most VW vehicles have forgone the the original air-cooled engines of the Type 1, the more current models have all opted to avail of a fluid-cooling system. Using coolants rather than air, emissions and engine noise can be kept within minimal levels. Regulation of coolant flow to react to the varying degrees of heat the engine undergoes is crucial in keeping the engine from under-performing due to the lack of heat or overheating. Cooling systems are always fitted with a VW thermostat, a small device that helps to keep the heat of the engine at optimal levels.

VW thermostats are mechanical in nature, usually using wax pellets contained inside a sealed chamber. The wax melts as the engine gets hotter, expanding throughout the chamber. Inside the containment of the wax pellet is a provision attached to a rod which opens the valves controlling coolant flow, which opens once the engines goes above the operating temperature i.e when the melted wax has melted and pushed the rod to a certain point. Since the composition of the wax determines the operating temperature, which in this case, is pretty much fixed, different type of wax is used for different driving applications. Most modern engines designed for lower emissions are typically fitted with VW thermostats that have a wax that has a higher operational temperature compared to older models. Just as much, sports cars have different wax pellets from MPV's or compact cars.

Installing the wrong VW thermostat or one that develops a malfunction can prove not only problematic but expensive due to the other areas that will be affected by engines with non-optimal temperatures. The least of the problems is poor fuel economy, but the worst case scenario would be overheating, which can severely damage other important parts, like warping the piston rings, overhead gaskets and kill the engine outright. It is strongly advised that maintenance of the thermostat, as well the entire cooling system is done routinely to avoid further implications and cause a substantial amount of cash in repairs.