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.

Bypass Air Control (BAC) Valve

Start engine. Disconnect air hose from BAC valve at port "A". See Fig 1 . When engine is cold, air (vacuum) should pass through valve. When engine is warm, air should NOT pass through valve. Replace valve as necessary.

Fig 1: Identifying BAC Valve

Courtesy of MAZDA MOTORS CORP.