it is the Secondary Air Injection Pump. it is for emissions. it pumps air into the exhaust to help heat the catalytic converter at cold start. it cost like $350. you dont want one it is just another part that can go bad:thumbsup:
Had to ask because all I have is a blank covering the opening. Looks like something belongs there and seemed strange that there would be a spot for something left open unless it was an option of some sort. Glad to not have it :thumbsup:
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