Solenoid valve

Electric vacuum solenoids are an essential component in the majority of internal combustion engines. Furthermore, due to their ‘recycling’ of exhaust fumes, while electric vacuum solenoids hardly bring cars up to ‘green’ standards of environmental friendliness, they do help reduce the quantity of noxious, toxic gases that cars unleash on the atmosphere. Thus, until the political and economic will to drive mass movement to the use of electric cars and engines reaches critical mass, their function remains vital to the fight against global warming.

Vacuum Solenoids

These electric vacuum solenoids, or ‘switching solenoids’ as they are commonly known, are vital to the process of exhaust gas recirculation, or EGR. Once fuel has passed through an engine, while it’s mostly a combination of relatively harmless nitrogen, water vapor and carbon dioxide, it also contains small quantities of noxious chemicals (the ones you hear so much about in the news) such as carbon monoxide, nitrogen oxide, and hydrocarbons, along with unburned fuel and particulate matter.

By the process of EGR, these gases are returned to the engine for a second round, with two effects. The one is the cooling down of the cylinder by the gas cocktail. The other is the unburned fuel being used on the second round through the engine, which of course means greater fuel efficiency. Many electric vacuum solenoids are activated by an increase in the vacuum produced by a working engine. Thus, when the engine ups its levels of exertion, the vacuum it produces increases, and the EGR valve opens, allowing a fixed quantity of the exhaust fumes in the valve’s proximity to return to the intake manifold (The intake manifold is the pipe that gathers together the air and exhaust fumes into one tube to be piped into the engine).
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