Part 2
1UR-FE ENGINE CONTROL SYSTEM: SFI SYSTEM: P0300-P0308: 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
DTC P0305 - Cylinder 5 Misfire Detected
DTC P0306 - Cylinder 6 Misfire Detected
DTC P0307 - Cylinder 7 Misfire Detected
DTC P0308 - Cylinder 8 Misfire Detected
(Continued)
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] Testing and Inspection.
NG -- REPLACE FUEL INJECTOR ASSEMBLY Removal
OK -- Continue to next step.
12. CHECK AIR INDUCTION SYSTEM
(a) Check the air induction system for vacuum leakage Intake System.
OK:
No leakage in air induction system.
NG -- REPAIR OR REPLACE AIR INDUCTION SYSTEM Removal
OK -- Continue to next step.
13. CHECK FUEL PRESSURE
(a) Check the fuel pressure Fuel System.
NG -- CHECK FUEL LINE
OK -- Continue to next step.
14. READ VALUE USING TECHSTREAM (COOLANT TEMP) P0171
NG -- REPLACE ENGINE COOLANT TEMPERATURE SENSOR Removal
OK -- Continue to next step.
15. READ VALUE USING TECHSTREAM (MAF)
(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 / All Data / MAF and Coolant Temp.
(e) Allow the engine to idle until Coolant Temp reaches 75°C (157°F) or higher.
(f) Read the MAF with the engine speed at 3000 rpm.
Standard:
Between 18.3 gm/sec. and 26.8 gm/sec. (shift lever: N; A/C: Off)
NG -- CHECK HARNESS AND CONNECTOR
OK -- Continue to next step.
16. CHECK VALVE TIMING P0011
NG -- ADJUST VALVE TIMING Reassembly
OK -- Continue to next step.
17. PERFORM ACTIVE TEST USING TECHSTREAM (CONTROL THE EGR STEP POSITION)
(a) Connect the Techstream to the DLC3.
(b) Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher.
HINT
* When performing the Active Test, make sure the shift lever is in P or N.
* The A/C switch and all accessory switches should be off.
(c) Turn the Techstream on.
(d) Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the EGR Step Position.
(e) Confirm the Throttle Idle Position is ON and check the engine idling condition and MAP values in the Data List while performing the Active Test.
HINT
* 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.
OK:
MAP and idling condition change in response to EGR step position as follows.
Standard:
NG -- INSPECT EGR VALVE
OK -- CHECK HARNESS AND CONNECTOR
18. INSPECT EGR VALVE
(a) Remove the EGR valve assembly Removal.
(b) Check if the EGR valve is stuck open.
OK:
EGR valve is tightly closed.
NG -- REPLACE EGR VALVE Removal
OK -- CHECK HARNESS AND CONNECTOR
19. CHECK AIR INDUCTION SYSTEM
(a) Check the air induction system for vacuum leakage Intake System.
OK:
No leakage in air induction system.
NG -- REPAIR OR REPLACE AIR INDUCTION SYSTEM Removal
OK -- Continue to next step.
20. CHECK FUEL PRESSURE
(a) Check the fuel pressure Fuel System.
NG -- CHECK FUEL LINE
OK -- Continue to next step.
21. READ VALUE USING TECHSTREAM (COOLANT TEMP) P0171
NG -- REPLACE ENGINE COOLANT TEMPERATURE SENSOR Removal
OK -- Continue to next step.
22. READ VALUE USING TECHSTREAM (MAF)
(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 / All Data / MAF and Coolant Temp.
(e) Allow the engine to idle until Coolant Temp reaches 75°C (157°F) or higher.
(f) Read the MAF with the engine speed at 3000 rpm.
Standard:
Between 18.3 gm/sec. and 26.8 gm/sec. (shift lever: N; A/C: Off)
NG -- CHECK HARNESS AND CONNECTOR
OK -- Continue to next step.
23. CHECK VALVE TIMING P0011
NG -- ADJUST VALVE TIMING Reassembly
OK -- Continue to next step.
24. PERFORM ACTIVE TEST USING TECHSTREAM (CONTROL THE EGR STEP POSITION)
(a) Connect the Techstream to the DLC3.
(b) Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher.
HINT
* When performing the Active Test, make sure the shift lever is in P or N.
* The A/C switch and all accessory switches should be off.
(c) Turn the Techstream on.
(d) Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the EGR Step Position.
(e) Confirm the Throttle Idle Position is ON and check the engine idling condition and MAP values in the Data List while performing the Active Test.
HINT
* 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.
OK:
MAP and idling condition change in response to EGR step position as follows.
Standard:
NG -- INSPECT EGR VALVE
OK -- INSPECT SPARK PLUG
25. INSPECT EGR VALVE
(a) Remove the EGR valve assembly Removal.
(b) Check if the EGR valve is stuck open.
OK:
EGR valve is tightly closed.
NG -- REPLACE EGR VALVE Removal
OK -- Continue to next step.
26. INSPECT SPARK PLUG
(a) Inspect the spark plug Testing and Inspection.
NG -- REPLACE SPARK PLUG Removal
OK -- Continue to next step.
27. CHECK FOR SPARKS AND IGNITION
(a) Perform the spark test Testing and Inspection.
NG -- CHANGE TO NORMAL SPARK PLUG AND CHECK SPARK OF MISFIRING CYLINDER
OK -- Continue to next step.
28. CHECK CYLINDER COMPRESSION PRESSURE
(a) Measure the cylinder compression pressure of the misfiring cylinder Engine.
NG -- CHECK ENGINE TO DETERMINE CAUSE OF LOW COMPRESSION
OK -- Continue to next step.
29. 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:
NG -- GO TO FUEL INJECTOR CIRCUIT Component Tests and General Diagnostics
OK -- Continue to next step.
30. CHECK FUEL INJECTOR OF MISFIRING CYLINDER
(a) Check the injector injection [whether fuel volume is high or low, and whether injection pattern is poor] Testing and Inspection.
NG -- REPLACE FUEL INJECTOR ASSEMBLY Removal
OK -- Continue to next step.
31. CHECK HARNESS AND CONNECTOR
(a) Check the connection and terminal contact pressure of connectors and wire harness between the mass air flow meter and ECM Electronic Circuit Inspection Procedure.
HINT
Repair any problems.
NEXT -- Continue to next step.
32. CHECK WHETHER DTC OUTPUT RECURS
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the Techstream on.
(d) Clear the DTC Reading and Clearing Diagnostic Trouble Codes.
(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 the Confirmation Driving Pattern.
(i) Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
(j) Input the DTC: P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307 or P0308.
(k) Check the DTC judgment result.
Result
B -- END
A -- Continue to next step.
33. HARNESS AND CONNECTOR (MASS AIR FLOW METER - ECM)
(a) Disconnect the MAF meter 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 -- Continue to next step.
34. REPLACE MASS AIR FLOW METER
(a) Replace the mass air flow meter assembly Removal.
HINT
If the results of the inspection performed in steps 15 and 22 indicates no problem, proceed to the next step without replacing the mass air flow meter assembly.
NEXT -- Continue to next step.
35. CHECK WHETHER DTC OUTPUT RECURS
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the Techstream on.
(d) Clear the DTC Reading and Clearing Diagnostic Trouble Codes.
(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 the Confirmation Driving Pattern.
(i) Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
(j) Input the DTC: P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307 or P0308.
(k) Check the DTC judgment result.
Result
B -- REPLACE ECM Removal
A -- END
36. 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 connectors.
(3) Ground the spark plug.
(4) Check if sparks occur while the engine is being cranked.
OK:
Sparks jump across electrode gap.
NG -- CHANGE TO NORMAL IGNITION COIL AND CHECK SPARK OF MISFIRING CYLINDER
OK -- REPLACE SPARK PLUG Removal
37. CHANGE TO NORMAL IGNITION COIL AND CHECK SPARK OF MISFIRING CYLINDER
(a) Change the ignition coil to an 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 connectors.
(3) Ground the spark plug.
(4) Check if sparks occur while the engine is being cranked.
OK:
Sparks jump across electrode gap.
NG -- REPLACE ECM Removal
OK -- REPLACE IGNITION COIL Removal
38. CHECK FUEL LINE
(a) Check the fuel lines for leaks or blockage.
NG -- REPAIR OR REPLACE FUEL LINE
OK -- REPLACE FUEL PUMP Removal