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      01-20-2013, 02:28 PM   #6
Stohlen
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Drives: AW 135i
Join Date: Aug 2012
Location: Waterford, Mi

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2008 BMW 135i  [2.83]
When you first start the engine, the vehicle starts in whats called "open loop". This is a feature of the obd2 system in which the engine controls the vehicle in a very inefficient manner that is intended to pollute as little as possible while warming the engine and the catalytic converters up to operating temperature. The engine is run at a higher rpm to accomplish this in less time because open loop is very bad on both gas and power. When the engine rpm drops down to normal (600-700 rpm) the vehicle goes into closed loop, which is the normal operating parameters of the engine.
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