ARV-Air Recirculation Valve. Kali cars in 84 and all 85's I believe. The ARV opens at cruise speeds/loads and allows some of the boost to "recirculate" to the intake side of the turbo. Not sure of the reason for this but it is %99.99999 chance emissions related. When I "disabled" mine I found the car much more responsive when the acclerator was pressed at highway speeds. I believe this is because the ARV allows boost to bleed off, when its disabled there is no lag time getting boost pressure up again. RT

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