Caution / Notice / Hint

WARNING: This page is about a different car, the 2016 Toyota Sienna. However, it is still accessible from the selected car via links, so may be relevant.

NOTE:

Inspect the fuses for circuits related to this system before performing the following inspection procedure.

HINT:

If any DTCs other than misfire DTCs are output, troubleshoot those DTCs first.
Read freeze frame data using the Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air fuel ratio was lean or rich, and other data from the time the malfunction occurred.
If the misfire does not recur when the vehicle is brought to the workshop, reproduce the conditions stored in the ECM as freeze frame data.
If the misfire still cannot be reproduced even though the conditions stored in the ECM as freeze frame data have been reproduced, one of the following factors is considered to be a possible cause of the problem:
1. There was insufficient fuel volume in the tank.
2. Improper fuel is used.
3. The spark plugs have been contaminated.
After finishing repairs, check the misfire counts of the cylinders ([Cylinder #1 Misfire Count to Cylinder #6 Misfire Count]).
Be sure to confirm that no misfiring cylinder DTCs are stored again by conducting the confirmation driving pattern after finishing repairs.
For 6 and 8 cylinder engines, the ECM intentionally does not store the specific misfiring cylinder DTCs at high engine speed. If misfires occur only in high engine speed areas, only DTC P0300 is stored.
In the event of DTC P0300 being present, perform the following operations:
1. Clear the DTC (Refer to DTC CHECK / CLEAR [12/2015 - 08/2016] ).
2. Start the engine and conduct the confirmation driving pattern.
3. Read the misfiring rates of each cylinder or DTC(s) using the Techstream.
4. Repair the cylinder(s) that has a high misfiring rate or is indicated by the DTC.
5. After finishing repairs, conduct the confirmation driving pattern again, in order to verify that DTC P0300 is not stored.
When one of Short FT #1, Long FT #1, Short FT #2 or Long FT #2 in the freeze frame data is outside the range of +/-15%, the air fuel ratio may be Rich (-15% or less) or Lean (+15% or more).
When the Coolant Temp in the freeze frame data is less than 75°C (167°F), the misfire has occurred only while warming up the engine.
An extremely imbalanced drive wheel which causes body vibration may cause misfire DTCs to be stored