The name Minneapolis is attributed to Charles Hoag, the city's first schoolteacher, who combined mni, a Dakota Sioux word for water, and polis, the Greek word for city.
EGR valve on top of the inlet manifold of a Saab H engine in a 1987 Saab 90. In internal combustion engines, exhaust gas recirculation (EGR) is a nitrogen oxide (NOx) emissions reduction technique used in petrol/gasoline and diesel engines. EGR works by recirculating a portion of an engine's exhaust gas back to the engine cylinders.
1 The EGR valve is vital to your car's emission controls. 2  Exhaust gas recirculation helps to keep huge amounts of unburned fuel from being released into the atmosphere. 3  This unburned fuel is thought to be a huge contributor to greenhouse gas build-up.ons. 1  When the EGR valve goes bad, it must be replaced. 2  Unlike some emissions control devices that can go bad without affecting the drivability of the car or truck, a bad EGR valve can really affect the engine's performance, or even cause it to stop running altogether. 3  The good news is you can clean it.