California Models

Data Trouble Code No. 25 - Air-Fuel Ratio Lean Malfunction

Detecting Condition
(A) Main heated oxygen sensor voltage is 0.45 volts or less (lean) for 90 seconds under the following conditions:
(2 trip detection)
^ Engine coolant temperature 70°C (161°F) or more.
^ Engine speed 1,500 rpm or more.
or
(B) Engine speed varies by more than 15 rpm over the preceding crank angle period during a period of 20 seconds or more under the following conditions (2 trip detection);
^ Engine speed idling.
^ Engine coolant temperature between 60°C (140°F) and 95°C (203°F).
or
(C) Difference of air/fuel ratio feedback compensation value between front (no. 1 - 3 cylinders) and rear (no. 4 - 6 cylinders) is more than 15 percentage for 20 seconds or more under the following conditions (2 trip detection);
^ Engine speed: 2,000 rpm or more.
^ Engine coolant temperature between 60°C (140°F) and 95°C (203°F).

Trouble Area
(A) ^ Open or short in main heated oxygen sensor circuit.
^ Main heated oxygen sensor.
^ Ignition system.
^ Engine Control Module.
or
(B/C) ^ Open or short in Injector circuit.
^ Fuel line pressure (injector leak or blockage).
^ Mechanical system malfunction (timing belt skipped).
^ Ignition system
^ Compression pressure.
^ Volume air flow meter.
^ Engine Control Module.

Malfunction Indicator Lamp
Normal Mode On
Test Mode On

Recorded in memory?
Yes