Toyota Avalon (XX50) 2019-2022 Service & Repair Manual: Random/Multiple Cylinder Misfire Detected (P030000,P030027,P030085-P030400)

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 stores a DTC.

When DTCs for misfiring cylinders are randomly stored, but DTC P030000 is not stored, it indicates that misfires have been detected in different cylinders at different times. DTC P030000 is only stored when several misfiring cylinders are detected at the same time.

MONITOR DESCRIPTION

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).

• Within the first 1000 crankshaft revolutions after the engine starts, an excessive number of misfires (approximately 10 to 70 misfires per 1000 crankshaft revolutions) occurs once.
• An excessive number of misfires (approximately 10 to 70 misfires per 1000 crankshaft revolutions) occurs a total of 4 times.

The ECM flashes the MIL (immediate 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.

• At a high engine speed, a sufficient amount of misfires to damage the catalyst occurring within 200 crankshaft revolutions is detected once.
• At a normal engine speed, a sufficient amount of misfires to damage the catalyst occurring within 200 crankshaft revolutions is detected 3 times.

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

MONITOR RESULT

Refer to detailed information in Checking Monitor Status.

Click here

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

CONFIRMATION DRIVING PATTERN

HINT:

• When clearing the permanent DTCs, refer to the "CLEAR PERMANENT DTC" procedure.

  Click here

• Permanent misfire and fuel system DTCs can only be cleared when performing the universal trip driving pattern when no malfunction is detected.

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 procedure).
6. Put the engine in Inspection Mode (Maintenance Mode).

   Click here

7. Using the Techstream, switch the ECM from normal mode to check mode.

   Click here

8. Start the engine.
9. Read the misfire counts of each cylinder, Misfire Count Cylinder #1 to Misfire Count Cylinder #4, with the engine idling. If any misfire count is displayed, skip the following confirmation driving pattern.
10. 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	4.5 minutes or more
    1000	4.5 minutes or more
    2000	2.5 minutes or more
    3000	1.5 minutes or more

11. Check whether misfires have occurred by checking DTCs and Freeze Frame Data.

    HINT:

    Do not turn the power 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.

12. Record the DTC(s), Freeze Frame Data and misfire counts.
13. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
14. Turn the power switch off and wait for at least 30 seconds.

WIRING DIAGRAM

Refer to DTC P010012 for the mass air flow meter sub-assembly circuit.

Click here

CAUTION / NOTICE / HINT

NOTICE:

• Inspect the fuses for circuits related to this system before performing the following procedure.
• Vehicle Control History may be stored in the hybrid vehicle control ECU assembly if the engine is malfunctioning. Certain vehicle condition information is recorded when Vehicle Control History is stored. Reading the vehicle conditions recorded in both the Freeze Frame Data and Vehicle Control History can be useful for troubleshooting.

  Click here

  (Select Powertrain in Health Check and then check the time stamp data.)

  Click here

• If any "Engine Malfunction" Vehicle Control History item has been stored in the hybrid vehicle control ECU assembly, make sure to clear it. However, as all Vehicle Control History items are cleared simultaneously, if any Vehicle Control History items other than "Engine Malfunction" are stored, make sure to perform any troubleshooting for them before clearing Vehicle Control History.

  Click here

HINT:

• In the past, when the primary ignition system (the igniter drive circuit in the ECM, the primary circuit in the ignition coil assembly, the related wire harness, or the connector) was out of order, diagnostic codes from P035113 to P035413 were output. However, these codes are not output in this vehicle.

  When a failure in the primary ignition system is suspected, refer to "Catalyst OT Misfire Fuel Cut History", "Catalyst OT Misfire Fuel Cut Cylinder #1 to #4", and "Misfire Count Cylinder #1 to #4" in the Freeze Frame Data, the pending Freeze Frame Data, and the Data List, and confirm in which cylinder the high-frequency misfire was concentrated.

• Referring to the following contents of the Freeze Frame Data (or the pending Freeze Frame Data) enables an estimation of which cylinder has misfired and to what degree.
  • Misfire Count Cylinder #1 to #4: Misfire count according to cylinder.
  • Catalyst OT Misfire Fuel Cut Cylinder #1 to #4: This expresses a high-frequency misfire was concentrated in a certain cylinder and that cylinder's fuel injection was stopped.
• If any DTCs other than misfire DTCs are output, troubleshoot those DTCs first.
• 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 (Misfire Count Cylinder #1 to Misfire Count Cylinder #4).
• Be sure to confirm that no misfiring cylinder DTCs are stored again by performing the confirmation driving pattern after finishing repairs.
• When one of Short FT B1S1, Long FT B1S1 in the Freeze Frame Data is outside the range of +/-20%, the air fuel ratio may be rich (-20% or less) or lean (+20% or higher).
• When Coolant Temperature in the Freeze Frame Data is less than 75°C (167°F), the misfires have occurred only while warming up the engine.
• Vehicle body vibration caused by an extremely imbalanced drive wheel may cause misfire DTCs to be stored.
• 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.

PROCEDURE

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(c) Turn the Techstream on.

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

(e) Read the DTCs.

HINT:

If any DTCs other than P030000, P030027, P030085, P030100, P030200, P030300 and/or P030400 are output, troubleshoot those DTCs first.

B

GO TO DTC CHART

A

(a) Check the PCV hose connections.

(b) Check the PCV valve.

Click here

OK:

PCV hose and PCV valve are connected correctly and are not damaged.

NG

REPAIR OR REPLACE PCV VALVE OR HOSE

OK

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(c) Turn the Techstream 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.

NEXT

(a) Enter the following menus: Powertrain / Engine / Data List / Catalyst OT Misfire Fuel Cut.

(b) Read the value displayed on the Techstream.

B

GO TO STEP 7

A

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(c) Turn the Techstream on.

(d) Using the Techstream, confirm the vehicle conditions recorded in the Freeze Frame Data which were present when the DTC was stored.

B

GO TO STEP 7

A

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(c) Turn the Techstream on.

(d) Put the engine in Inspection Mode (Maintenance Mode).

(e) Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher.

(f) Enter the following menus: Powertrain / Engine / Active Test / Prohibit the Catalyst OT Misfire Prevent Fuel Cut / Data List / Coolant Temperature, Injection Mode and Misfire Count Cylinder #1 to Misfire Count Cylinder #4.

(g) Read each value for Misfire Count Cylinder #1 to Misfire Count Cylinder #4 and Injection Mode displayed on the Techstream while performing the Active Test.

A

GO TO STEP 8

B

GO TO STEP 11

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(c) Turn the Techstream on.

(d) Put the engine in Inspection Mode (Maintenance Mode).

(e) Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher.

(f) Enter the following menus: Powertrain / Engine / Active Test / Control the Injection Mode / Data List / Coolant Temperature, Injection Mode and Misfire Count Cylinder #1 to Misfire Count Cylinder #4.

(g) According to the display on the Techstream, read the Data List with the Active Test "Control the Injection Mode" set to Port. If no misfire counts occur in any cylinders, perform procedure [A] and [B] and then check the misfire counts again.

(1) 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].

CAUTION:

When performing a driving test, obey all speed limits and traffic laws.

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

B

GO TO STEP 11

A

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(c) Turn the Techstream on.

(d) Put the engine in Inspection Mode (Maintenance Mode).

(e) Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher.

(f) Enter the following menus: Powertrain / Engine / Active Test / Control the Injection Mode / Data List / Coolant Temperature, Injection Mode and Misfire Count Cylinder #1 to Misfire Count Cylinder #4.

(g) According to the display on the Techstream, read the Data List with the Active Test "Control the Injection Mode" set to Direct. If no misfire counts occur in any cylinders, perform procedure [A] and [B] and then check the misfire counts again.

(1) 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].

CAUTION:

When performing a driving test, obey all speed limits and traffic laws.

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

HINT:

Perform "Inspection After Repair" after replacing the port fuel injector assembly.

Click here

A

GO TO STEP 14

B

GO TO STEP 17

C

REPLACE PORT FUEL INJECTOR ASSEMBLY (MISFIRING CYLINDER)

D

(a) Check the fuel pressure (for low pressure side).

Click here

HINT:

Perform "Inspection After Repair" after replacing the port fuel injector assembly.

Click here

OK

REPLACE PORT FUEL INJECTOR ASSEMBLY (MISFIRING CYLINDER)

NG

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

HINT:

Perform "Inspection After Repair" after replacing the fuel pump (for low pressure side).

Click here

OK

REPLACE FUEL PUMP (FOR LOW PRESSURE SIDE)

NG

REPAIR OR REPLACE FUEL SYSTEM

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(c) Turn the Techstream on.

(d) Put the engine in Inspection Mode (Maintenance Mode).

(e) Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher.

(f) Enter the following menus: Powertrain / Engine / Active Test / Control the Injection Mode / Data List / Coolant Temperature, Injection Mode and Misfire Count Cylinder #1 to Misfire Count Cylinder #4.

(g) According to the display on the Techstream, read the Data List with the Active Test "Control the Injection Mode" set to Direct. If no misfire counts occur in any cylinders, perform procedure [A] and [B] and then check the misfire counts again.

(1) 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].

CAUTION:

When performing a driving test, obey all speed limits and traffic laws.

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

HINT:

Perform "Inspection After Repair" after replacing the direct fuel injector assembly.

Click here

A

REPLACE DIRECT FUEL INJECTOR ASSEMBLY

B

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(c) Turn the Techstream on.

(d) Clear the DTCs.

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

NEXT

(a) Turn the power switch on (IG).

(b) Turn the Techstream on.

(c) Put the engine in Inspection Mode (Maintenance Mode).

(d) Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher.

(e) Enter the following menus: Powertrain / Engine / Data List / Coolant Temperature, Injection Mode, Misfire Count Cylinder #1 to Misfire Count Cylinder #4, Misfire RPM and Misfire Load.

(f) Drive the vehicle with Misfire RPM and Misfire Load.

CAUTION:

When performing a driving test, obey all speed limits and traffic laws.

(g) Monitor all of the misfire count values and Injection Mode displayed on the Techstream.

HINT:

Perform "Inspection After Repair" after replacing the direct fuel injector assembly.

Click here

A

CHECK FOR INTERMITTENT PROBLEMS

C

GO TO STEP 17

D

REPLACE DIRECT FUEL INJECTOR ASSEMBLY

B

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

Click here

HINT:

Perform "Inspection After Repair" after replacing the spark plug.

Click here

NG

REPLACE SPARK PLUG

OK

(a) Perform a spark test.

Click here

HINT:

• If the result of the spark test is normal, proceed to the next step.
• Perform "Inspection After Repair" after replacing the spark plug or ignition coil assembly.

  Click here

NEXT

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

Click here

HINT:

Perform "Inspection After Repair" after repairing or replacing the engine assembly.

Click here

OK

REPLACE ECM

NG

CHECK ENGINE TO DETERMINE CAUSE OF LOW COMPRESSION

(a) Check the intake system for vacuum leaks.

Click here

OK:

No leaks from intake system.

HINT:

Perform "Inspection After Repair" after repairing or replacing the intake system.

Click here

NG

REPAIR OR REPLACE INTAKE SYSTEM

OK

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(c) Turn the Techstream on.

(d) Enter the following menus: Powertrain / Engine / Data List / Coolant Temperature.

(e) Read the Data List twice, when the engine is both cold and warmed up.

Standard:

HINT:

Perform "Inspection After Repair" after replacing the engine coolant temperature sensor.

Click here

NG

REPLACE ENGINE COOLANT TEMPERATURE SENSOR

OK

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(c) Turn the Techstream on.

(d) Put the engine in Inspection Mode (Maintenance Mode).

(e) Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher.

(f) Enter the following menus: Powertrain / Engine / Data List / Engine Speed, Mass Air Flow Sensor and Coolant Temperature.

(g) Read Mass Air Flow Sensor while maintaining an engine speed of 2500 rpm.

HINT:

During charge control, the engine speed is set at idle. Therefore, the engine speed will not increase when the accelerator pedal is depressed. In this case, read the Data List after charge control has completed.

Standard:

NG

GO TO STEP 26

OK

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(c) Turn the Techstream on.

(d) Put the engine in Inspection Mode (Maintenance Mode).

(e) Start the engine and warm it up until the engine coolant temperature is 75°C (167°F) or higher.

HINT:

The A/C switch and all accessories should be off.

(f) Enter the following menus: Powertrain / Engine / Active Test / Control the EGR Step Position / Data List / Intake Manifold Absolute Pressure, Coolant Temperature and Engine Independent.

(g) Confirm that the value of Data List item Engine Independent is "Operate" then check the value of Intake Manifold Absolute Pressure while performing the Active Test.

NOTICE:

• Make sure that the value of Data List item Engine Independent is "Operate" while performing the Active Test.
• Do not leave the EGR valve open for 10 seconds or more during the Active Test.
• Be sure to return the EGR valve to step 0 when the Active Test is completed.
• Do not open the EGR valve 30 steps or more during the Active Test.

OK:

The value of Intake Manifold Absolute Pressure changes in response to the EGR step position when the value of Engine Independent is "Operate".

Standard:

HINT:

• If the value of Data List item Engine Independent is "Not Opr" when the engine is idling, charge control is being performed. Perform the Active Test after charge control is complete ("Operate" is displayed).
• While performing the Active Test, if the increase in the value of Intake Manifold Absolute Pressure is small, the EGR valve assembly may be a malfunctioning.
• Even if the EGR valve assembly is malfunctioning, rough idling or an increase in the value of Intake Manifold Absolute Pressure may occur while performing the Active Test. However, the amount that the value of Intake Manifold Absolute Pressure increases will be smaller than normal.

OK

GO TO STEP 22

NG

(a) Remove the EGR valve assembly.

Click here

(b) Check if the EGR valve is stuck open.

OK:

EGR valve is tightly closed.

HINT:

Perform "Inspection After Repair" after replacing the EGR valve assembly.

Click here

NG

REPLACE EGR VALVE ASSEMBLY

OK

(a) Remove the cylinder head cover sub-assembly.

Click here

(b) Turn the crankshaft pulley and align its groove with the TDC timing mark of the timing chain cover.

(c) Check that the timing marks of the camshaft timing gear assembly and camshaft timing exhaust gear assembly are at the positions shown in the illustration. HINT: If the timing marks are not as shown, turn the crankshaft one revolution clockwise. OK: Timing marks on camshaft timing gear assembly and camshaft timing exhaust gear assembly are at the positions shown in the illustration. HINT: If the result is not as specified, check for mechanical malfunctions that may have affected the valve timing, such as a jumped tooth or stretching of the timing chain.

*a Timing Mark *b TDC Timing Mark *c Groove

OK

GO TO STEP 26

NG

(a) Check for mechanical malfunctions that affect the valve timing, such as a jumped tooth or stretching of the timing chain.

HINT:

Perform "Inspection After Repair" after repairing or replacing the engine mechanical system.

Click here

NG

REPAIR OR REPLACE MALFUNCTIONING PARTS, COMPONENT AND AREA

OK

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(c) Turn the Techstream on.

(d) Clear the DTCs.

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

NEXT

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

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

(c) Input the DTC: P030000, P030027, P030085, P030100, P030200, P030300 or P030400.

(d) Check the DTC judgment result.

A

CHECK FOR INTERMITTENT PROBLEMS

B

GO TO STEP 26

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

Click here

HINT:

Repair any problems.

NEXT

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(c) Turn the Techstream on.

(d) Clear the DTCs.

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

NEXT

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

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

(c) Input the DTC: P030000, P030027, P030085, P030100, P030200, P030300 or P030400.

(d) Check the DTC judgment result.

A

END

B

(a) Disconnect the mass air flow meter sub-assembly connector.

(b) Disconnect the ECM connector.

(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

(a) Replace the mass air flow meter sub-assembly.

Click here

HINT:

• If the results of the inspections performed in step 19 (READ VALUE USING TECHSTREAM (MASS AIR FLOW SENSOR)) indicated no problem, proceed to the next step without replacing the mass air flow meter sub-assembly.
• Perform "Inspection After Repair" after replacing the mass air flow meter sub-assembly.

  Click here

NEXT

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(c) Turn the Techstream on.

(d) Clear the DTCs.

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

NEXT

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

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

(c) Input the DTC: P030000, P030027, P030085, P030100, P030200, P030300 or P030400.

(d) Check the DTC judgment result.

A

END

B

REPLACE ECM