Troubleshooting

DTC P0306 Cylinder 6 Misfire Detected

CIRCUIT DESCRIPTION

DTC Detecting Condition:

Misfire: The ECM uses the crankshaft position sensor and camshaft position sensor to monitor changes in the crankshaft rotation for each cylinder.

The ECM counts the number of times the engine speed change rate indicates that misfire has occurred. And when the misfire rate equals or exceeds the count indicating that the engine condition has deteriorated, the MIL lights up.

If the misfire rate is high enough and the driving conditions will cause catalyst overheating, the MIL blinks when misfiring occurs.

HINT: When codes for a misfiring cylinder is recorded repeatedly but no random misfire code is recorded, it indicates that the misfires were detected and recorded at different times.

Wiring Diagram:

CONFIRMATION DRIVING PATTERN
a. Connect the LEXUS hand-held tester or OBD II scan tool to the DLC3.
b. Record DTC and the freeze frame data.
c. Use the LEXUS hand-held tester to set to the check mode.
d. Drive the vehicle several times with the engine speed, load and its surrounding range shown with the ENGINE SPD, CALC LOAD in the freeze frame data or the MISFIRE RPM, MISFIRE LOAD in the data list.
If you have no LEXUS hand-held tester, turn the ignition switch OFF after the symptom is simulated the first time. Then repeat the simulation process again.






HINT: In order to memorize DTC of misfire, it is necessary to drive around the MISFIRE RPM, MISFIRE LOAD in the data list for the given period of time.

e. Check whether there is misfire or not by monitoring DTC and the freeze frame data. After that, record them.
f. Turn the ignition switch OFF and wait at least 5 seconds.

Step 1:

Step 2:

Step 3 - 4:

Step 4 (Continued) - 7:

INSPECTION PROCEDURE