If you have to transport gasoline or propane in your vehicle, make sure they are sealed tightly, that the cans/tanks stay upright, and keep your windows open to avoid fumes from building up. An engine flush product, on the other hand, is designed solely to clean. More information https://telegra.ph/The-Thrill-of-Ten-Exploring-Cars-with-V10-Engines-05-31 Suggested by Martin B. Grab the garden hose and rinse the underside of the hood using a light spray. You could also use a pressure hose using the lowest pressure setting. The idea is to avoid dousing the engine bay with strong water gushes to prevent issues later. THERMOSTAT FAILURE. The bi-metallic principle is used in a rarer type of sensor. Movement of a bi-metallic strip inside a heating coil in the sensor opens a pair of contacts, cutting off the current to the heater and the gauge. With the current off the strip cools and straightens out, remaking the contact so that current flows again. This sequence is repeated rapidly, with the amount of time the contacts are closed (and the amount of time that currents flows to the gauge) depending on the overall temperature of the sensor unit. One of the most important things you can do to extend your engine's life is to regularly change your oil and oil filter. Changing engine oil every 3,000 miles used to be necessary, but modern cars can generally go longer between changes, often between 5,000 and 15,000 miles. Consult your owner's manual or dealership service department for the proper interval for your vehicle and the correct oil to use if you change it yourself. You'll also need a filter, a filter wrench, a drain pan, and rags for cleanup.