- High temperature misfire occurs in Three-Way Catalytic Converter (TWC) (MIL blinks)
- Emission deterioration misfire occurs (MIL illuminates)
| Last Modified: 11-29-2007 | 1.6 C | |
| Service Category: Engine/Hybrid System | Section: Engine Control | |
| Model Year: 2008 | Model: Sequoia | Doc ID: RM000000XH306IX |
| Title: 3UR-FE ENGINE CONTROL: SFI SYSTEM: DESCRIPTION (2008 Sequoia) | ||
|
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 |
|
DTC |
P0305 |
Cylinder 5 Misfire Detected |
|
DTC |
P0306 |
Cylinder 6 Misfire Detected |
|
DTC |
P0307 |
Cylinder 7 Misfire Detected |
|
DTC |
P0308 |
Cylinder 8 Misfire Detected |
DESCRIPTION
When the engine misfires, high concentrations of hydrocarbons (HC) enter the exhaust gas. Extremely high HC concentration levels can cause increases in exhaust emission levels. High concentrations of HC can also cause increases in the Three-Way Catalytic Converter (TWC) temperature, which may cause damage to the TWC. To prevent these increases in emissions and to limit the possibility of thermal damage, the ECM monitors the misfire rate. When the temperature of the TWC reaches the point of thermal degradation, the MIL blinks. To monitor misfires, the ECM uses both the Camshaft Position (CMP) sensor and the Crankshaft Position (CKP) sensor. The CMP sensor is used to identify any misfiring cylinders and the CKP sensor is used to measure variations in the crankshaft rotation speed. Misfires are counted as when the crankshaft rotation speed variations exceed predetermined thresholds.
If the misfire rate exceeds the threshold level, the ECM illuminates the MIL and stores a DTC.
|
DTC No. |
DTC Detection Condition |
Trouble Area |
|---|---|---|
|
P0300 |
Simultaneous misfiring of several cylinders occurs and one of following conditions below is detected (2 trip detection logic): |
|
|
P0301 P0302 P0303 P0304 P0305 P0306 P0307 P0308 |
Misfiring of specific cylinder occurs and one of following conditions below is detected (2 trip detection logic):
|
When multiple DTCs for misfiring cylinders are 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 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 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 stores a DTC when either one of the following conditions, which could cause the Three-Way Catalytic Converter (TWC) damage, is detected (2 trip detection logic).
- At a high engine rpm, a catalyst damage misfire, which monitored every 200 crankshaft revolutions, occurs once.
- At a normal engine rpm, a catalyst damage misfire, which monitored every 200 crankshaft revolutions, occurs 3 times.
HINT:
If a catalyst damage misfire occurs, the ECM informs the driver by flashing the MIL.
MONITOR STRATEGY
|
Related DTCs |
P0300: Multiple cylinder misfire P0301: Cylinder 1 misfire P0302: Cylinder 2 misfire P0303: Cylinder 3 misfire P0304: Cylinder 4 misfire P0305: Cylinder 5 misfire P0306: Cylinder 6 misfire P0307: Cylinder 7 misfire P0308: Cylinder 8 misfire |
|
Required Sensors/Components (Main) |
Crankshaft position sensor and Camshaft position sensor |
|
Required Sensors/Components (Related) |
Engine coolant temperature and intake air temperature sensors and Mass air flow meter |
|
Frequency of Operation |
Continuous |
|
Duration |
1000 to 4000 crankshaft revolutions: Emission related misfire 200 to 600 crankshaft revolutions: Catalyst damaged misfire |
|
MIL Operation |
2 driving cycles: MIL illuminates when misfire detect MIL flashes immediately: When catalyst damaged misfire occur |
|
Sequence of Operation |
None |
TYPICAL ENABLING CONDITIONS
Misfire
|
Monitor runs whenever following DTCs not present |
P0102 - P0103 (MAF meter) P0110 - P0113 (IAT sensor) P0115 - P0118 (ECT sensor) P0120 - P0223, P2135 (TP sensor) P0125 (Insufficient ECT for Closed Loop) P0327, P0328 (Knock sensor) P0335 (CKP sensor) P0500 (VSS) |
|
Battery voltage |
8 V or more |
|
VVT system |
Not operated by scan tool |
|
Engine RPM |
400 to 5900 rpm |
|
Either of following conditions (a) or (b) met |
- |
|
(a) ECT at engine start |
More than -7°C (19°F) |
|
(b) ECT |
More than 20°C (68°F) |
|
Fuel cut |
OFF |
Monitor Period of Emission-Related-Misfire
|
First 1000 revolutions after engine start, or Check Mode |
Crankshaft 1000 revolutions |
|
Except above |
Crankshaft 1000 revolutions x 4 |
Monitor Period of Catalyst-Damaged-Misfire (MIL Blinks)
|
All of following conditions 1, 2 and 3 met |
Crankshaft 200 revolutions x 3 |
|
1. Driving cycles |
1st |
|
2. Check mode |
OFF |
|
3. Engine RPM |
Less than 2800 rpm |
|
Except above |
Crankshaft 200 revolutions |
TYPICAL MALFUNCTION THRESHOLDS
Monitor Period of Emission-Related-Misfire
|
Misfire rate |
1.5% or more |
Monitor Period of Catalyst-Damaged-Misfire (MIL Blinks)
|
Number of misfire per 200 revolutions |
103 or more (varies with intake air amount and RPM) |
MONITOR RESULT
Refer to Checking Monitor Status
.
WIRING DIAGRAM
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.
-
Using the Techstream, switch the ECM from normal mode to check mode
.
- Read the misfire counts of each cylinder (cylinder No. 1 to No. 8) with the engine in an idling condition. If any misfire count is displayed, skip the following confirmation driving pattern.
-
Drive the vehicle several times with the conditions, such as engine rpm and engine load, shown in Misfire RPM and Misfire Load in the Data List.
HINT:
In order to store misfire DTCs, it is necessary to operate the vehicle for the period of time shown in the table below, with the Misfire RPM and Misfire Load in the Data List.
Engine RPM
Duration
Idling
3.5 minutes or more
1000
3 minutes or more
2000
1.5 minutes or more
3000
1 minute or more
-
Check whether misfires have occurred by checking DTCs and freeze frame data.
HINT:
Do not turn the ignition 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.
- Record the DTC(s), freeze frame data and misfire counts.
- Turn the ignition switch off and wait for at least 5 seconds.
INSPECTION PROCEDURE
HINT:
- If any DTCs other than misfire DTCs are output, troubleshoot those DTCs first.
- Read freeze frame data using the Techstream. Freeze frame data records the engine condition when malfunctions are detected. 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 freeze frame data.
-
If the misfire still cannot be reproduced even though the conditions stored in the freeze frame data have been duplicated, one of the following factors is considered to be a possible cause of the problem:
- The fuel level is low.
- Improper fuel is used.
- The spark plugs are dirty.
- After finishing repairs, check that no misfires occur in each cylinder (cylinder No. 1, No. 2, No. 3, No. 4, No. 5, No. 6, No. 7 and No. 8).
- Be sure to confirm that no misfiring cylinder DTCs are stored again by conducting the confirmation driving pattern, after the repairs.
-
For 6 and 8 cylinder engines, the ECM intentionally does not stored the specific misfiring cylinder DTCs at high engine RPM. If misfires only occur during high engine RPM driving, only DTC P0300 is stored.
In the event of DTC P0300 being present, perform the following operations:
-
Clear the DTC
.
- Start the engine and conduct the confirmation driving pattern.
- Read the misfiring rates of each cylinder or DTC(s) using the Techstream.
- Repair the cylinder(s) that has a high misfiring rate or is indicated by the DTC.
- After finishing repairs, conduct the confirmation driving pattern again, in order to verify that DTC P0300 is not stored.
-
Clear the DTC
- When either Short FT #1, Long FT #1, Short FT #2 or Long FT #2 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 more).
- When the Coolant Temp in the freeze frame data is less than 75°C (167°F), the misfires occurred only while warming up the engine.
- An extremely imbalanced drive wheel, which causes body vibration, may cause misfire DTCs detection.
PROCEDURE
|
1. |
CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO MISFIRE CODES) |
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the Techstream on.
(d) Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
(e) Read DTCs.
Result
|
Result |
Proceed to |
|---|---|
|
P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307 and/or P0308 are output |
A |
|
P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307 and/or P0308 and other DTCs are output |
B |
HINT:
If any DTCs other than P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307 and P0308 are output, troubleshoot those DTCs first.
|
|
2. |
READ VALUE USING TECHSTREAM (MISFIRE RPM AND MISFIRE LOAD) |
(a) Connect the Techstream the DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the Techstream on.
(d) Enter the following menus: Powertrain / Engine and ECT / Data List / Misfire / 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.
|
|
3. |
CHECK PCV HOSE CONNECTIONS |
(a) Check the PCV hose connections.
OK:
PCV hose is connected correctly and is not damaged.
|
|
4. |
READ VALUE USING TECHSTREAM |
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the Techstream on.
(d) Enter the following menus: Powertrain / Engine and ECT / Data List / Catalyst OT MF F/C.
(e) Read the value displayed on the Techstream.
Result
|
Data List |
Tester Display |
Proceed to |
|---|---|---|
|
Catalyst OT MF F/C |
AVAIL (Avail) |
A |
|
NOT AVL (Not Avl) |
B |
|
|
5. |
PERFORM ACTIVE TEST USING TECHSTREAM |
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the Techstream on.
(d) Enter the following menus: Powertrain / Engine and ECT / 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 either idling or being revved within 3000 rpm.
|
|
6. |
READ VALUE USING TECHSTREAM (MISFIRE COUNT) |
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the Techstream on.
(d) Clear DTCs
.
(e) Enter the following menus: Powertrain / Engine and ECT / Data List / Misfire / Cylinder #1 Misfire Rate, #2, #3, #4, #5, #6, #7 and #8.
(f) Allow the engine to idle.
(g) Read each value for CYL #1 to #8 (Cylinder #1 Misfire Rate to #8) displayed on the Techstream. If no misfire counts occur in any cylinders, perform the following procedures:
(1) Move the shift lever to D.
(2) Check the CYL #1 to #8 (Cylinder #1 Misfire Rate to #8).
(3) If misfire counts are still not displayed, perform procedure "A" and "B" and then check the misfire counts again.
(h) Drive the vehicle with the Misfire RPM and Misfire Load noted in the "Read value using Techstream (Misfire RPM and Misfire Load)" procedures above (Procedure "A").
(i) Read the CYL #1 to #8 (Cylinder #1 Misfire Rate to #8) or DTCs displayed on the Techstream (Procedure "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's record of the ECT is below 75°C (167°F), the misfire may be detected only when the engine is cold.
- If the freeze frame data's record of the Engine Run Time is below 120 seconds, the misfire may be detected immediately after the engine is started.
|
|
7. |
INSPECT SPARK PLUG |
(a) Remove the ignition coil and the spark plug of the misfiring cylinder
.
(b) Measure the spark plug electrode gap.
Standard gap:
1.0 to 1.1 mm (0.0394 to 0.0433 in.)
(c) Check the electrode for carbon deposits.
Recommended Spark Plug
|
Manufacturer |
Product |
|---|---|
|
DENSO |
SK20HR11 |
NOTICE:
If the electrode gap is larger than standard, replace the spark plug. Do not adjust the electrode gap.
|
|
8. |
CHECK FOR SPARKS AND IGNITION |
(a) Disconnect the injector connectors to prevent the engine from starting.
CAUTION:
Always disconnect all injector connectors.
NOTICE:
Do not crank the engine for more than 2 seconds.
(b) Remove the ignition coil from the cylinder head
.
(c) Install the spark plug onto the ignition coil.
(d) Attach the spark plug assembly to the cylinder head.
(e) Crank the engine for less than 2 seconds and check the spark.
OK:
Sparks jump across electrode gap.
(f) Install the ignition coil.
(g) Reconnect the injector connectors.
|
|
9. |
CHECK CYLINDER COMPRESSION PRESSURE |
(a) Measure the cylinder compression pressure of the misfiring cylinder
.
|
|
10. |
INSPECT ECM TERMINAL OF MISFIRING CYLINDER (#10, #20, #30, #40, #50, #60, #70 AND/OR #80 VOLTAGE) |
(a) Disconnect the ECM connector.
(b) Turn the ignition switch to ON.
(c) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
|
Tester Connection |
Switch Condition |
Specified Condition |
|---|---|---|
|
D56-86 (#10) - D56-43 (E01) |
Ignition switch ON |
11 to 14 V |
|
D56-109 (#20) - D56-43 (E01) |
Ignition switch ON |
11 to 14 V |
|
D56-85 (#30) - D56-43 (E01) |
Ignition switch ON |
11 to 14 V |
|
D56-108 (#40) - D56-43 (E01) |
Ignition switch ON |
11 to 14 V |
|
D56-84 (#50) - D56-43 (E01) |
Ignition switch ON |
11 to 14 V |
|
D56-107 (#60) - D56-43 (E01) |
Ignition switch ON |
11 to 14 V |
|
D56-83 (#70) - D56-43 (E01) |
Ignition switch ON |
11 to 14 V |
|
D56-106 (#80) - D56-43 (E01) |
Ignition switch ON |
11 to 14 V |
|
|
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]
.
|
|
12. |
CHECK AIR INDUCTION SYSTEM |
(a) Check the air induction system for vacuum leakage
.
OK:
No leakage from air induction system.
|
|
13. |
CHECK VALVE TIMING
|
|
|
14. |
CHECK FUEL PRESSURE |
(a) Check the fuel pressure
.
|
|
15. |
READ VALUE USING TECHSTREAM (COOLANT TEMP)
|
|
|
16. |
READ VALUE USING TECHSTREAM (MAF)
|
|
|
17. |
CHECK AIR INDUCTION SYSTEM |
(a) Check the air induction system for vacuum leakage
.
OK:
No leakage from air induction system.
|
|
18. |
CHECK VALVE TIMING
|
|
|
19. |
CHECK FUEL PRESSURE |
(a) Check the fuel pressure
.
|
|
20. |
READ VALUE USING TECHSTREAM (COOLANT TEMP)
|
|
|
21. |
READ VALUE USING TECHSTREAM (MAF)
|
|
|
22. |
INSPECT SPARK PLUG |
(a) Remove the ignition coil and the spark plug of the misfiring cylinder
.
(b) Measure the spark plug electrode gap.
Standard gap:
1.0 to 1.1 mm (0.0394 to 0.0433 in.)
(c) Check the electrode for carbon deposits.
Recommended Spark Plug
|
Manufacturer |
Product |
|---|---|
|
DENSO |
SK20HR11 |
NOTICE:
If the electrode gap is larger than standard, replace the spark plug. Do not adjust the electrode gap.
|
|
23. |
CHECK FOR SPARKS AND IGNITION |
(a) Disconnect the injector connectors to prevent the engine from starting.
CAUTION:
Always disconnect all injector connectors.
NOTICE:
Do not crank the engine for more than 2 seconds.
(b) Remove the ignition coil from the cylinder head
.
(c) Install the spark plug onto the ignition coil.
(d) Attach the spark plug assembly to the cylinder head.
(e) Crank the engine for less than 2 seconds and check the spark.
OK:
Sparks jump across electrode gap.
(f) Install the ignition coil.
(g) Reconnect the injector connectors.
|
|
24. |
CHECK CYLINDER COMPRESSION PRESSURE |
(a) Measure the cylinder compression pressure of the misfiring cylinder
.
|
|
25. |
INSPECT ECM TERMINAL OF MISFIRING CYLINDER (#10, #20, #30, #40, #50, #60, #70 AND/OR #80 VOLTAGE) |
(a) Disconnect the ECM connector.
(b) Turn the ignition switch to ON.
(c) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
|
Tester Connection |
Switch Condition |
Specified Condition |
|---|---|---|
|
D56-86 (#10) - D56-43 (E01) |
Ignition switch ON |
11 to 14 V |
|
D56-109 (#20) - D56-43 (E01) |
Ignition switch ON |
11 to 14 V |
|
D56-85 (#30) - D56-43 (E01) |
Ignition switch ON |
11 to 14 V |
|
D56-108 (#40) - D56-43 (E01) |
Ignition switch ON |
11 to 14 V |
|
D56-84 (#50) - D56-43 (E01) |
Ignition switch ON |
11 to 14 V |
|
D56-107 (#60) - D56-43 (E01) |
Ignition switch ON |
11 to 14 V |
|
D56-83 (#70) - D56-43 (E01) |
Ignition switch ON |
11 to 14 V |
|
D56-106 (#80) - D56-43 (E01) |
Ignition switch ON |
11 to 14 V |
|
|
26. |
CHECK FUEL INJECTOR OF MISFIRING CYLINDER |
(a) Check the injector injection [whether fuel volume is high or low, and whether injection pattern is poor]
.
|
|
27. |
CHANGE TO NORMAL SPARK PLUG AND CHECK SPARK OF MISFIRING CYLINDER |
(a) Change the installed spark plug to a spark plug that functions normally.
(b) Perform a spark test.
CAUTION:
Always disconnect all injector connectors.
NOTICE:
Do not crank the engine for more than 2 seconds.
(1) Install the spark plug to the ignition coil and connect the ignition coil connector.
(2) Disconnect the injector connector.
(3) Ground the spark plug.
(4) Check if sparks occur while the engine is being cranked.
OK:
Sparks jump across electrode gap.
|
|
28. |
CHANGE TO NORMAL IGNITION COIL AND CHECK SPARK OF MISFIRING CYLINDER |
(a) Change the ignition coil to a ignition coil that functions normally.
(b) Perform a spark test.
CAUTION:
Always disconnect all injector connectors.
NOTICE:
Do not crank the engine for more than 2 seconds.
(1) Install the spark plug to the ignition coil and connect the ignition coil connector.
(2) Disconnect the injector connector.
(3) Ground the spark plug.
(4) Check if sparks occur while the engine is being cranked.
OK:
Sparks jump across electrode gap.
|
|
|