Toyota Venza: Random / Multiple Cylinder Misfire Detected (P0300-P0304)

Toyota Venza Service Manual / 1ar-fe Engine Control / Sfi System / Random / Multiple Cylinder Misfire Detected (P0300-P0304)

DESCRIPTION

When the engine misfires, high concentrations of hydrocarbons (HC) enter the exhaust gas. Extremely high hydrocarbon concentration levels can cause an increase in exhaust emission levels. Extremely high concentrations of hydrocarbons 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 count. 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 sensor and the crankshaft position 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.

DTC No.	DTC Detection Condition	Trouble Area
P0300	Simultaneous misfiring of several cylinders occurs and one of the following conditions is met (2 trip detection logic). A misfire occurs that may damage the three-way catalytic converter (MIL blinks when detect immediately). An emission deterioration misfire occurs (MIL illuminates).	Open or short in engine wire harness Connector connection Vacuum hose connections Ignition system Fuel injector Fuel pressure Mass air flow meter Engine coolant temperature sensor Compression pressure Valve timing PCV valve and hose PCV hose connections Intake system Intake air control valve actuator (for tumble control valve) ECM
P0301 P0302 P0303 P0304	Misfiring of a specific cylinder occurs and one of the following conditions is met (2 trip detection logic). A misfire occurs that may damage the three-way catalytic converter (MIL blinks when detect immediately). An emission deterioration misfire occurs (MIL illuminates).

DTC No.

DTC Detection Condition

Trouble Area

P0300

Simultaneous misfiring of several cylinders occurs and one of the following conditions is met (2 trip detection logic).

A misfire occurs that may damage the three-way catalytic converter (MIL blinks when detect immediately).
An emission deterioration misfire occurs (MIL illuminates).

Open or short in engine wire harness
Connector connection
Vacuum hose connections
Ignition system
Fuel injector
Fuel pressure
Mass air flow meter
Engine coolant temperature sensor
Compression pressure
Valve timing
PCV valve and hose
PCV hose connections
Intake system
Intake air control valve actuator (for tumble control valve)
ECM

P0301

P0302

P0303

P0304

Misfiring of a specific cylinder occurs and one of the following conditions is met (2 trip detection logic).

A misfire occurs that may damage the three-way catalytic converter (MIL blinks when detect immediately).
An emission deterioration misfire occurs (MIL illuminates).

When DTCs for misfiring cylinders are randomly stored, but DTC P0300 is not stored, it indicates that misfires have been detected in different cylinders at different times. DTC P0300 is only stored when several misfiring cylinders are detected at the same time.

MONITOR DESCRIPTION

The ECM illuminates the MIL and stores a DTC immediately when either one of the following conditions, which could cause emission deterioration, is detected (2 trip detection logic).

Within the first 1000 crankshaft revolutions after the engine starts, an excessive number of misfires (approximately 20 to 50 misfires per 1000 crankshaft revolutions) occurs once.
An excessive number of misfires (approximately 20 to 50 misfires per 1000 crankshaft revolutions) occurs a total of 4 times.

The ECM flashes the MIL (immediately detection logic) and stores a DTC (2 trip detection logic) when either one of the following conditions, which could cause damage to the three-way catalytic converter, is detected.

HINT:

If a catalyst-damaging misfire occurs, the monitor informs the driver by blinking the MIL.

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.

The ECM illuminates the MIL and stores a DTC when either one of the following conditions, which could cause emission deterioration, is detected (2 trip detection logic).

MONITOR STRATEGY

Related DTCs	P0300: Multiple Cylinder Misfire P0301: Cylinder 1 Misfire P0302: Cylinder 2 Misfire P0303: Cylinder 3 Misfire P0304: Cylinder 4 Misfire
Required Sensors/Components (Main)	Crankshaft position sensor Camshaft position sensor
Required Sensors/Components (Related)	Engine coolant temperature Intake air temperature sensor Mass air flow meter
Frequency of Operation	Continuous
Duration	1000 crankshaft revolutions (soon after engine is started: 1 time, other 4 times) (Emission-related misfire) 200 crankshaft revolutions (1 or 3 times) (Catalyst-damaging misfire)
MIL Operation	2 driving cycles: Emission-related misfire MIL flashes immediately: Catalyst-damaging misfire
Sequence of Operation	None

TYPICAL ENABLING CONDITIONS

Misfire

Monitor runs whenever following DTCs not stored	P0016 (VVT System - Misalignment) P0017 (Exhaust VVT System - Misalignment) P0102, P0103 (Mass Air Flow Meter) P0112, P0113 (Intake Air Temperature Sensor) P0115, P0117, P0118 (Engine Coolant Temperature Sensor) P0125 (Insufficient Coolant Temperature for Closed Loop Fuel Control) P0120, P0121, P0122, P0123, P0220, P0222, P0223, P2135 (Throttle Position Sensor) P0327, P0328 (Knock Sensor) P0335 (Crankshaft Position Sensor) P0340 (Camshaft Position Sensor) P0351 - P0354 (Igniter) P0500 (Vehicle Speed Sensor) P0705 (Shift Lever Position Switch)
Battery voltage	8 V or higher
VVT system	Not operated by scan tool
Engine speed	400 to 6100 rpm
Either of following conditions (a) or (b) met	-
(a) Engine coolant temperature at engine start	Higher than -7°C (19°F)
(b) Engine coolant temperature	Higher than 20°C (68°F)
Fuel cut	OFF

Monitor Period of Emission-related Misfire

First 1000 revolutions after engine start, or during check mode	Crankshaft 1000 revolutions
Except above	Crankshaft 1000 revolutions x 4

Monitor Period of Catalyst-damaging Misfire (MIL Blinks)

All of following conditions 1, 2, 3 and 4 met	Crankshaft 200 revolutions x 3
Except above (MIL blinks immediately)	Crankshaft 200 revolutions
1. Driving cycles	1st
2. Check mode	OFF
3. Engine speed	Less than 2300 rpm
4. Intake air amount per revolution	Less than 1.05 g/rev

TYPICAL MALFUNCTION THRESHOLDS

Monitor Period of Emission-related Misfire

Misfire rate

2.041% or more

Monitor Period of Catalyst-damaging Misfire (MIL Blinks)

Number of misfires per 200 revolutions

124 or more (varies with intake air amount and engine speed)

MONITOR RESULT

Refer to Checking Monitor Status (See page
).

CONFIRMATION DRIVING PATTERN

Connect the Techstream to the DLC3.
Turn the ignition switch to ON.
Turn the Techstream on.
Record the DTC(s) and freeze frame data.
Clear the DTCs (even if no DTCs are stored, perform the Clear DTC procedure) (See page ).

Using the Techstream, switch the ECM from normal mode to check mode (See page ).

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.

Drive the vehicle so that the vehicle conditions displayed in Misfire RPM and Misfire Load of the Data List are the same as the freeze frame data. Perform this step several times.

HINT:

In order to store misfire DTCs, it is necessary to operate the vehicle for the period of time shown in the table below, confirm the Misfire RPM and Misfire Load in the Data List.

Engine speed	Duration
Idling	8.0 minutes or more
1000	4.5 minutes or more
2000	2.5 minutes or more
3000	1.5 minutes or more

Check whether misfires have occurred by checking DTCs and freeze frame data.
HINT:

Do not turn the ignition switch off until the output 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 are cleared.
Record the DTC(s), freeze frame data and misfire counts.
Turn the ignition switch off and wait for at least 30 seconds.
Clear the DTCs (even if no DTCs are stored, perform the Clear DTC procedure) (See page ).

WIRING DIAGRAM

Refer to DTC P0102 (See page ).

Refer to Fuel Injector Circuit (See page ).

CAUTION / NOTICE / HINT

HINT:

Check the "Fuel Cut Elps Time" in the Data List or the Freeze Frame Data.
If the elapsed time is over 0 seconds, then the engine speed is high (engine speed at which fuel cut occurs + 500 rpm).

When this has happened, there is the possibility that the No. 1 valve rocker arm sub-assembly will become loose and a fire could start, so check that the valve rocker arm is properly attached (See page ).
By clearing the DTC, "Fuel Cut Elps Time" will be cleared.
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 in the tank.
2. Improper fuel was used.
3. The spark plugs have been contaminated.
4. The problem requires further diagnosis.
After finishing repairs, check the misfire counts of the cylinders (Cylinder #1 Misfire Count to Cylinder #4 Misfire Count).
Be sure to confirm that no misfiring cylinder DTCs are stored again by conducting the confirmation driving pattern after finishing repairs.
When one of Short FT #1 or Long FT #1 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 Coolant Temp in the freeze frame data is below 75°C (167°F), the misfires have occurred only while warming up the engine.
An extremely imbalanced drive wheel which causes body vibration may cause misfire DTCs to be stored.

PROCEDURE

1.	CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO MISFIRE DTCS)

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(d) Enter the following menus: Powertrain / Engine / Trouble Codes.

(e) Read the DTCs.

HINT:

Write down the output DTCs.

Result	Proceed to
DTC P0300, P0301, P0302, P0303 and/or P0304 are output	A
DTC P0300, P0301, P0302, P0303 and/or P0304 and other DTCs are output	B

HINT:

If any DTCs other than P0300, P0301, P0302, P0303 and P0304 are output, troubleshoot those DTCs first.

GO TO DTC CHART

2.	CHECK PCV HOSE CONNECTIONS

(a) Check the PCV hose connections (See page ).

OK:

PCV hose is correctly connected and is not damaged.

REPAIR OR REPLACE PCV HOSE

3.	READ VALUE USING TECHSTREAM (MISFIRE RPM AND MISFIRE LOAD)

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(d) Enter the following menus: Powertrain / Engine / Data List / Misfire RPM and Misfire Load.

(e) Read and note the Misfire RPM and Misfire Load values.

HINT:

The Misfire RPM and Misfire Load values indicate the vehicle conditions under which the misfire occurred.

4.	READ VALUE USING TECHSTREAM (CATALYST OT MF F/C)

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(d) Enter the following menus: Powertrain / Engine / Data List / Catalyst OT MF F/C.

(e) Read the value displayed on the Techstream.

Data List	Techstream Display	Proceed to
Catalyst OT MF F/C	Avail	A
Catalyst OT MF F/C	Not Avl	B

GO TO STEP 6

5.	PERFORM ACTIVE TEST USING TECHSTREAM

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(d) Enter the following menus: Powertrain / Engine / Active Test / Prohibit the Catalyst OT Misfire prevent F/C.

(e) Perform the Active Test.

NOTICE:

When performing the Active Test, make sure the vehicle is stopped and the engine is either idling or being revved within 3000 rpm.

6.	READ VALUE USING TECHSTREAM (CYLINDER #1 (to #4) MISFIRE COUNT)

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(d) Enter the following menus: Powertrain / Engine / Data List / Gas Misfire / Cylinder #1 Misfire Count, Cylinder #2 Misfire Count, Cylinder #3 Misfire Count and Cylinder #4 Misfire Count.

(e) Start the engine and allow the engine to idle.

(f) Read each value for Cylinder #1 Misfire Count to Cylinder #4 Misfire Count displayed on the Techstream. If no misfire counts occur in any cylinders, perform procedure [A] and [B] and then check the misfire counts again.

(g) Drive the vehicle with the Misfire RPM and Misfire Load noted in the "Read Value Using Techstream (Misfire RPM and Misfire Load)" procedures above [A].

(h) Read the Cylinder #1 Misfire Count to Cylinder #4 Misfire Count or DTCs displayed on the Techstream [B].

Result

Result	Proceed to
Most misfires occur in only 1 or 2 cylinders	A
3 cylinders or more have equal misfire counts	B

HINT:

If it is difficult to reproduce misfires for each cylinder, check the Data List item called Misfire Margin. Try to find vehicle driving conditions that lower the Misfire Margin value. Values above 30% are considered normal.
If the freeze frame data record of the engine coolant temperature is below 75°C (167°F), the misfire may be detected only when the engine is cold.
If the freeze frame data record of the Engine Run Time is below 120 seconds, the misfire may be detected immediately after the engine is started.

GO TO STEP 18

7.	INSPECT SPARK PLUG

(a) Inspect the spark plug of the misfiring cylinder (See page ).

HINT:

Perform "Inspection After Repair" after replacing the spark plug (See page ).

REPLACE SPARK PLUG

8.	CHECK FOR SPARK (SPARK TEST)

(a) Perform a spark test (See page ).

HINT:

If the result of the spark test is normal, proceed to the next step.
Perform "Inspection After Repair" after repairing or replacing the ignition system (See page ).

9.	CHECK CYLINDER COMPRESSION PRESSURE

(a) Measure the cylinder compression pressure of the misfiring cylinder (See page ).

HINT:

Perform "Inspection After Repair" after repairing or replacing the engine assembly (See page ).

CHECK ENGINE TO DETERMINE CAUSE OF LOW COMPRESSION

10.	CHECK HARNESS AND CONNECTOR (POWER SOURCE OF FUEL INJECTOR ASSEMBLY)

(a) Disconnect the ECM connector.

(b) Turn the ignition switch to ON.

Standard Voltage:

Tester Connection	Switch Condition	Specified Condition
B58-85 (#10) - B58-109 (E01)	Ignition switch ON	11 to 14 V
B58-84 (#20) - B58-109 (E01)	Ignition switch ON	11 to 14 V
B58-83 (#30) - B58-109 (E01)	Ignition switch ON	11 to 14 V
B58-82 (#40) - B58-109 (E01)	Ignition switch ON	11 to 14 V

GO TO FUEL INJECTOR CIRCUIT

11.	CHECK FUEL INJECTOR OF MISFIRING CYLINDER

(a) Check the injector injection (whether fuel volume is high or low, and whether injection pattern is poor) (See page ).

HINT:

Perform "Inspection After Repair" after replacing the fuel injector assembly (See page ).

REPLACE FUEL INJECTOR

12.	CHECK INTAKE SYSTEM

(a) Check the intake system for vacuum leaks (See page ).

OK:

No leaks from intake system.

HINT:

Perform "Inspection After Repair" after repairing or replacing the intake system (See page ).

REPAIR OR REPLACE INTAKE SYSTEM

13.	CHECK INTAKE AIR CONTROL VALVE ACTUATOR (FOR TUMBLE CONTROL VALVE)

(a) Check the intake air control valve actuator for tumble control valve (See page ).

REPLACE INTAKE AIR CONTROL VALVE ACTUATOR (FOR TUMBLE CONTROL VALVE)

14.	CHECK FUEL PRESSURE

(a) Check the fuel pressure (See page ).

GO TO STEP 34

15.	READ VALUE USING TECHSTREAM (COOLANT TEMP)

REPLACE ENGINE COOLANT TEMPERATURE SENSOR

16.	READ VALUE USING TECHSTREAM (MAF)

GO TO STEP 29

17.	CHECK VALVE TIMING

GO TO STEP 29

GO TO STEP 35

18.	CHECK INTAKE SYSTEM

(a) Check the intake system for vacuum leaks (See page ).

OK:

No leaks from intake system.

HINT:

Perform "Inspection After Repair" after repairing or replacing the intake system (See page ).

REPAIR OR REPLACE INTAKE SYSTEM

19.	CHECK INTAKE AIR CONTROL VALVE ACTUATOR (FOR TUMBLE CONTROL VALVE)

(a) Check the intake air control valve actuator for tumble control valve (See page ).

REPLACE INTAKE AIR CONTROL VALVE ACTUATOR (FOR TUMBLE CONTROL VALVE)

20.	CHECK FUEL PRESSURE

(a) Check the fuel pressure (See page ).

GO TO STEP 34

21.	READ VALUE USING TECHSTREAM (COOLANT TEMP)

REPLACE ENGINE COOLANT TEMPERATURE SENSOR

22.	READ VALUE USING TECHSTREAM (MAF)

GO TO STEP 29

23.	CHECK VALVE TIMING

GO TO STEP 35

24.	INSPECT SPARK PLUG

(a) Inspect the spark plug of the misfiring cylinder (See page ).

HINT:

Perform "Inspection After Repair" after replacing the spark plug (See page ).

REPLACE SPARK PLUG

25.	CHECK FOR SPARK (SPARK TEST)

(a) Perform a spark test (See page ).

HINT:

If the result of the spark test is normal, proceed to the next step.
Perform "Inspection After Repair" after repairing or replacing the ignition system (See page ).

26.	CHECK CYLINDER COMPRESSION PRESSURE

(a) Measure the cylinder compression pressure of the misfiring cylinder (See page ).

HINT:

Perform "Inspection After Repair" after repairing or replacing the engine assembly (See page ).

CHECK ENGINE TO DETERMINE CAUSE OF LOW COMPRESSION

27.	CHECK HARNESS AND CONNECTOR (POWER SOURCE OF FUEL INJECTOR ASSEMBLY)

(a) Disconnect the ECM connector.

(b) Turn the ignition switch to ON.

Standard Voltage:

Tester Connection	Switch Condition	Specified Condition
B58-85 (#10) - B58-109 (E01)	Ignition switch ON	11 to 14 V
B58-84 (#20) - B58-109 (E01)	Ignition switch ON	11 to 14 V
B58-83 (#30) - B58-109 (E01)	Ignition switch ON	11 to 14 V
B58-82 (#40) - B58-109 (E01)	Ignition switch ON	11 to 14 V

GO TO FUEL INJECTOR CIRCUIT

28.	CHECK FUEL INJECTOR OF MISFIRING CYLINDER

(a) Check the injector injection (whether fuel volume is high or low, and whether injection pattern is poor) (See page ).

HINT:

Perform "Inspection After Repair" after replacing the fuel injector assembly (See page ).

REPLACE FUEL INJECTOR

29.	CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER CONNECTOR CONNECTION)

(a) Check the connection and terminal contact pressure of connectors and wire harnesses between the mass air flow meter and ECM (See page ).

HINT:

Repair any problems.

30.	CHECK WHETHER DTC OUTPUT RECURS

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(d) Clear the DTCs (See page ).

(e) Turn the ignition switch off and wait for at least 30 seconds.

(f) Turn the ignition switch to ON and turn the Techstream on.

(g) Start the engine and warm it up.

(h) Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.

(i) Enter the following menus: Powertrain / Engine / Utility / All Readiness.

(j) Input the DTC: P0300, P0301, P0302, P0303 or P0304.

(k) Check the DTC judgment result.

Result

Proceed to

ABNORMAL

(DTC P0300, P0301, P0302, P0303 or P0304 is output)

NORMAL

(DTC is not output)

END

31.	CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - ECM)

REPAIR OR REPLACE HARNESS OR CONNECTOR

32.	REPLACE MASS AIR FLOW METER

(a) Replace the mass air flow meter (See page ).

HINT:

If the results of the inspections performed in steps 16 and 22 indicated no problem, proceed to the next step without replacing the mass air flow meter.
Perform "Inspection After Repair" after replacing the mass air flow meter (See page ).

33.	CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(d) Clear the DTCs (See page ).

(e) Turn the ignition switch off and wait for at least 30 seconds.

(f) Turn the ignition switch to ON and turn the Techstream on.

(g) Start the engine and warm it up.

(h) Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.

(i) Enter the following menus: Powertrain / Engine / Utility / All Readiness.

(j) Input the DTC: P0300, P0301, P0302, P0303 or P0304.

(k) Check the DTC judgment result.

Result

Proceed to

NORMAL

(DTC is not output)

ABNORMAL

(DTC P0300, P0301, P0302, P0303 or P0304 is output)

END

REPLACE ECM

34.	CHECK FUEL LINE

(a) Check the fuel lines for leaks or blockage.

HINT:

Perform "Inspection After Repair" after replacing the fuel pump (See page ).

REPLACE FUEL PUMP

REPAIR OR REPLACE FUEL LINE

35.	CHECK ENGINE MECHANICAL SYSTEM

REPAIR OR REPLACE MALFUNCTIONING PARTS, COMPONENT AND AREA

36.	CHECK WHETHER DTC OUTPUT RECURS

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(d) Clear the DTCs (See page ).

(e) Turn the ignition switch off and wait for at least 30 seconds.

(f) Turn the ignition switch to ON and turn the Techstream on.

(g) Start the engine and warm it up.

(h) Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.

(i) Enter the following menus: Powertrain / Engine / Utility / All Readiness.

(j) Input the DTC: P0300, P0301, P0302, P0303 or P0304.

(k) Check the DTC judgment result.

Result

Result	Proceed to
DTC is not output	A
DTC P0300, P0301, P0302, P0303 or P0304 is output	B

CHECK FOR INTERMITTENT PROBLEMS

REPLACE ECM

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