LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Mazda >> 1985 >> GLC Base >> Repair and Diagnosis >> Engine Performance >> System >> Feedback Carburetor System >> Testing >> Vacuum Switch
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Vacuum Switch

  1. The 3 vacuum switches are located on the firewall behind the carburetor. The individual switches can be identified by wiring color code of electrical connector. Unplug electrical connector and vacuum hoses.
  2. Connect a vacuum source and circuit tester to each valve and check their calibration.
  3. On No. 1 switch, connect a circuit tester to Blue/Red and Green/Yellow terminals. The switch should be off at .8 in. Hg and on at 4.3-5.1 in. Hg.
  4. Connect circuit tester to Blue/White and Green/Yellow terminals. The switch should be off at .9 in. Hg and on at 7.5-8.3 in. Hg. No. 3 switch has same color codes and is tested in the same manner.
  5. On No. 2 switch, connect circuit tester to Yellow/Green and Black terminals. The switch should be off at 1.2 in. Hg and on at 13.8-15.4 in. Hg.
scientia non olet · About LEMON Manuals