Regal V6-231 3.8L Turbo VIN 9 FI (1984)
Distributor Vacuum Control: Description and Operation
Distributor Vacuum Modulator Valve (DVMV)
This valve has a calibration point of 8.7 inches of vacuum. Whenever manifold or ported vacuum is less than the calibration point, the DVMV
switches to full manifold vacuum. Whenever the manifold or ported vacuum is greater than the calibration point, the DVMV switches to the highest
vacuum, either manifold or ported.