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Vacuum RESTRICTOR

Orifice-type flow restrictor is used in emission calibrations to control flow rate and/or ignition timing. Restrictor can be found in EGR valve system (opening and closing), part throttle spark advance, purge system and thermactor system. Calibration changes with application but flow rate through restrictor is equal in both directions. If blocked, replace restrictor.

VACUUM RESTRICTOR IDENTIFICATION

Color Hole Size In. (mm)
Blue .015 (.38)
Red .020 (.51)
Orange .024 (.61)
Yellow .030 (.76)
Green .050 (1.27)