LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Toyota >> 1984 >> Tercel Base >> Repair and Diagnosis >> Engine Performance >> Testing & Diagnosis >> High Altitude Compensation System >> System Testing >> High Altitude Check
October 30: LEMON manuals on a temporary server, it is slow and having issues, download the manuals you need! Later in November we will switch back to the fast server.

High Altitude Check

  1. Warm up engine and check ignition timing at idle. Disconnect vacuum hose from distributor sub-diaphragm and plug hose end.
  2. Check that ignition timing remains stationary for more than 1 minute. Stop engine and reconnect hose to check valve.
    Fig 1: High Altitude Compensation System
    G38380Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  3. Disconnect 2 hoses on top of HAC valve. Blow air into each hose and check that air flows into carburetor. Reconnect hoses to proper locations.