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2ZR-FXE ENGINE CONTROL: SFI SYSTEM: P0300-P0304: Random / Multiple Cylinder Misfire Detected
DTC P0300 - Random / Multiple Cylinder Misfire Detected
DTC P0301 - Cylinder 1 Misfire Detected
DTC P0302 - Cylinder 2 Misfire Detected
DTC P0303 - Cylinder 3 Misfire Detected
DTC P0304 - Cylinder 4 Misfire Detected
DESCRIPTION
When the engine misfires, high concentrations of hydrocarbons (HC) enter the exhaust gas. High HC concentration levels can cause an increase in exhaust emission levels. Extremely high concentrations of HC can also cause increases in the three-way catalytic converter temperature, which may cause damage to the three-way catalytic converter. To prevent this increase in emissions and to limit the possibility of thermal damage, the ECM monitors the misfire rate. When the temperature of the three-way catalytic converter reaches the point of thermal degradation, the ECM blinks the MIL. To monitor misfires, the ECM uses both the Camshaft Position (CMP) sensor and the Crankshaft Position (CKP) sensor. The camshaft position sensor is used to identify any misfiring cylinders and the crankshaft position sensor is used to measure variations in the crankshaft rotation speed. Misfires are counted when the crankshaft rotation speed variations exceed predetermined thresholds. If the misfire count exceeds the threshold levels, and could cause emission control system performance deterioration, the ECM illuminates the MIL and sets a DTC.
When DTCs for misfiring cylinders are randomly set, but DTC P0300 is not set, it indicates that misfires have been detected in different cylinders at different times. DTC P0300 is only set when several misfiring cylinders are detected at the same time.
MONITOR DESCRIPTION
The ECM illuminates the MIL and sets a DTC when either one of the following conditions, which could cause emission control system performance deterioration, is detected (2 trip detection logic).
- Within the first 1000 crankshaft revolutions of the engine starting, an excessive misfiring rate (approximately 20 to 50 misfires per 1000 crankshaft revolutions) occurs once.
- An excessive misfiring rate (approximately 20 to 50 misfires per 1000 crankshaft revolutions) occurs a total of 4 times.
The ECM flashes the MIL and sets a DTC when either one of the following conditions, which could cause the three-way catalytic converter damage, is detected (2 trip detection logic).
HINT
If a catalyst damage misfire occurs, the monitor informs the driver by blinking the MIL (1 trip).
- In every 200 crankshaft revolutions at a high engine speed, the threshold misfiring percentage is recorded once.
- In every 200 crankshaft revolutions at a normal engine speed, the threshold misfiring percentage is recorded 3 times.
Misfire Monitor for Mexico Models
The ECM illuminates the MIL and sets a DTC when either one of the following conditions, which could cause emission deterioration, is detected (2 trip detection logic).
- Within the first 1000 crankshaft revolutions of the engine starting, an excessive misfiring rate (approximately 1000 misfires per 1000 crankshaft revolutions) occurs once.
- An excessive misfiring rate (approximately 500 misfires per 1000 crankshaft revolutions) occurs a total of 4 times.
The ECM flashes the MIL and sets a DTC when the following condition, which could cause the three-way catalytic converter damage, is detected (2 trip detection logic).
- A catalyst damage misfire, which is monitored every 200 crankshaft revolutions, occurs 3 times.
MONITOR STRATEGY
TYPICAL ENABLING CONDITIONS
Misfire
Monitor Period of Emission-Related Misfire
Monitor Period of Catalyst Damaging Misfire (MIL Blinks)
FOR MEXICO MODELS:
Misfire: for Mexico models
Monitor period of emission-related-misfire: for Mexico models
Monitor period of catalyst-damaged-misfire (MIL blinks): for Mexico models
TYPICAL MALFUNCTION THRESHOLDS
Monitor Period of Emission Related Misfire
Monitor Period of Catalyst Damaging Misfire (MIL Blinks)
FOR MEXICO MODELS:
Monitor period of emission-related-misfire: for Mexico models
Monitor period of catalyst-damaged-misfire (MIL blinks): for Mexico models
MONITOR RESULT
Refer to detailed information in Checking Monitor Status Mode 6 Data.
P0300: Misfire / EWMA MISFIRE
P0300: Misfire / MISFIRE RATE
P0301: Misfire / EWMA MISFIRE1
P0301: Misfire / MISFIRE RATE1
P0302: Misfire / EWMA MISFIRE2
P0302: Misfire / MISFIRE RATE2
P0303: Misfire / EWMA MISFIRE3
P0303: Misfire / MISFIRE RATE3
P0304: Misfire / EWMA MISFIRE4
P0304: Misfire / MISFIRE RATE4
HINT
*: EWMA (Exponential Weighted Moving Average) misfire counts for last 10 driving cycles (calculated) Calculation: 0.1 x (current counts) + 0.9 x (previous average). Initial value for (previous average) = 0
WIRING DIAGRAM
Fuel injector circuit: Refer to Fuel Injector Circuit Fuel Injector Circuit.
Mass air flow meter circuit: Refer to DTC P0102 P0102.
CONFIRMATION DRIVING PATTERN
1. Connect the Techstream to the DLC3.
2. Turn the power switch on (IG).
3. Turn the Techstream on.
4. Record the DTC(s) and freeze frame data.
5. Clear the DTCs (even if no DTCs are stored, perform the clear DTC operation) Reading and Clearing Diagnostic Trouble Codes.
6. Put the engine in inspection mode (maintenance mode) Component Tests and General Diagnostics.
7. Using the Techstream, switch the ECM from normal mode to check mode Check Mode Procedure.
8. Read the misfire counts of each cylinder, Cylinder #1 Misfire Count to Cylinder #4 Misfire Count, with the engine idling. If any misfire count is displayed, skip the following confirmation driving pattern.
9. Drive the vehicle several times with the conditions, such as engine speed and engine load, shown in Misfire RPM and Misfire Load in the freeze frame data.
HINT
In order to store misfire DTCs, it is necessary to operate the vehicle for the period of time shown in the table below, using the Misfire RPM and Misfire Load in the Data List.
10. Check whether misfires have occurred by checking DTCs and freeze frame data.
HINT
Do not turn the power switch off until the stored DTC(s) and freeze frame data have been recorded. When the ECM returns to normal mode (default), the stored DTC(s), freeze frame data and other data will be cleared.
11. Record the DTC(s), freeze frame data and misfire counts.
12. Turn the power switch off and wait for at least 5 seconds.
13. Clear the DTCs (even if no DTCs are stored, perform the clear DTC operation) Reading and Clearing Diagnostic Trouble Codes