secondary air pump. runs when the car just starts and is cold. It's an emissions thing. You moved the camera really close the SAP during the film and the sound got very loud. Sounds like that's where it's coming from.
Originally Posted by BBBoy323i
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A person filled with excessive and single-minded zeal
BMW VIN Decoder
Last edited by WDE46; 05-05-2013 at 02:19 PM.