Toyota 4Runner P0421 Code: Meaning, Causes, How to Fix

P0421 is a relatively rare OBDII trouble code.   It’s generic, which means it has the same definition for the Toyota 4Runner as it would any other vehicle. It is technically defined as “Warm Up Catalyst Efficiency → Below Threshold (Bank 1)”. In layman’s terms, it indicates that your Toyota 4Runner’s catalytic converter is not scrubbing pollutants efficiently … Read more

Toyota 4Runner P0316: Engine Misfire → At Startup

A relatively common, yet difficult to diagnose OBD-II trouble code is P0316. It has the same meaning for the Toyota 4Runner as it would any other vehicle.  It indicates that there is a misfire at the startup of the vehicle, and that it happens within the first 1000 revolutions of the engine. P0316: Engine Misfire … Read more

Toyota 4Runner P0740: Torque Converter Clutch Circuit Malfunction

P0740 is one of the most common transmission trouble codes. It means that the 4Runner‘s computer has detected that there is an issue with the torque converter clutch (TCC) solenoid circuit.     P0740: Torque Converter Clutch Circuit Malfunction   The TCC “locks” the drivetrain, which allows for a true mechanical connection between the transmission … Read more

Toyota 4Runner P0160: O2 Sensor → No Activity Detected B2S2

  P0160 is a standard OBDII trouble code. It has the same meaning for any vehicle with OBDII, including the Toyota 4Runner. When a vehicle has P0160, the PCM/ECM is not detecting any activity from the sensor.  It doesn’t mean that the O2 sensor isn’t getting power, but that the voltage isn’t changing, which is … Read more