Lexus - Toyota OBD1 Diagnostic Trouble Code
26
Air Fuel Ratio Rich
Area
Bad ground connection
* Check, clean, tighten all ground connections.
Open in E1(ground) circuit
Short in injector circuit
* Test the circuit from the ECM connector checking for values specified in factory service manual.
Fuel pressure regulator diaphragm breached
Fuel injectors leaking
Open or short in cold start injector circuit
Cold Start injector leaking
Open or short in heated oxygen sensor circuit
Upstream oxygen sensor
Engine coolant temperature sensor
Volume air flow meter (AFM)
Engine Control Module(ECM)
Diagnosis
Heated oxygen sensor output is less than 0.45 V for at least 90 seconds. when heated oxygen sensor is warmed up (racing at 2.000 rpm) and drive at 50 – 100 km/h
When the engine speed varies by more than 15 rpm over the preceding crankshaft position period during a period of 50 seconds during idling with the engine coolant temperature 75’C (167’F) or more.