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.
One of the most common symptoms of a problem with the vehicleâs EGR valve is a rough idle. It is not uncommon for EGR valves to malfunction and become stuck in the open position. This can lead to exhaust gas recirculation to occur causing a rough idle even when the conditions are not desirable.