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.

Diagnostic Aids

A lean condition can be caused by a vacuum leak, fuel pressure too low, water in fuel or an exhaust leak around manifold or in front of O2S.

If the front O2S and the rear HO2S voltage reading is less than 300 mV all the time, the oxygen sensors are probably not at fault.