BLOX RACING MAP BYPASS VALVES - TYPE D :: INTAKE MANIFOLD MOUNTED GUN METALThe BLOX Racing MAP Bypass Valve is designed for use with forced induction applications. The MAP Bypass Valve completely blocks boost from reaching the MAP sensor, thus simulating a wide open throttle reading at the vehicle's ECU. The vehicle is then prevented from running in "limp" mode so that no check engine light appears. The end result is protecting the MAP sensor from being damaged. MAP Bypass Valves are available as internal or external units.