2007 Toyota Sienna P0304 cylinder misfire

2007 Toyota Sienna

Toyota Sienna On the 2007 Toyota Sienna, The P0304 is pointing to a misfire on Cylinder #4. This is the middle cylinder on the side of the engine closest to the front of the vehicle. More commonly, this is due to a faulty Spark Plug, Ignition Coil or Fuel Injector issue. So, best place to start is by inspecting the spark plug. Look for any signs of cracks in the body and/or a worn diode. If there are any doubts, replace all the spark plugs. If the plug checks ok, you can…

Read More

2006 Toyota Sienna P0057 Oxygen Sensor

2006 Toyota Sienna

Toyota Sienna On the 2006 Toyota Sienna,  the “Sensor 2’s” (aka “Downstream”) sensors are NOT A/F Sensors. They are “Heated Oxygen Sensors“. Only the “Sensor 1’s” (aka “upstream”) Sensors are A/F (Air/Fuel Ratio) Sensors. So… with the P0057, this is pointing to a fault with the internal heater for the Bank2 Sensor2 Oxygen Sensor. The on-board computer uses this internal heater to get the sensor to normal operating temps within a matter of seconds on cold starts. When it tries to activate the heater and sees no response, the P0057…

Read More