P050B

1UR-FE ENGINE CONTROL: SFI SYSTEM: P050B: Cold Start Ignition Timing Performance
P050B - Cold Start Ignition Timing Performance

DESCRIPTION

This monitor will run when the engine is started at an engine coolant temperature of -10 to 50°C (14 to 122°F). The DTC will be stored after the engine idles for 13 seconds (2 trip detection logic).

The DTC is designed to monitor the ignition timing at cold start. When the engine is started at an engine coolant temperature of below 50°C (122°F), the ECM checks the ignition timing during engine idling. If the ignition timing advances beyond the specified level within 10 seconds, the ECM interprets this as a malfunction. The MIL is illuminated and a DTC is stored when the malfunction is detected in consecutive driving cycles (2 trip detection logic).

NOTICE:
When the cable is disconnected from the negative battery terminal during inspections or repairs, the ISC (Idle Speed Control) learned values are cleared. This DTC cannot be stored with the ISC learned values cleared.

HINT
ISC learning is performed when the engine is warmed up and has been idling for 5 minutes.









WIRING DIAGRAM

Refer to DTC P0102 P0102.

MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS





TYPICAL MALFUNCTION THRESHOLDS





CONFIRMATION DRIVING PATTERN





1. Connect the Techstream to the DLC3.

2. Turn the engine switch on (IG) and turn the Techstream on.

3. Clear DTCs (even if no DTCs are stored, perform the clear DTC operation).

4. Turn the engine switch off and wait for at least 30 seconds.

5. Turn the engine switch on (IG) and turn the Techstream on [A].

6. Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Coolant Temp.

7. Check that "Coolant Temp" in the Data List is within the range of -10 to 50°C (14 to 122°F).

8. Start the engine and warm it up until the coolant temperature is the same as the coolant temperature in the freeze frame data.

9. Idle the engine for 1 minute or more [B].

10. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes [C].

11. Read the pending DTCs.

HINT
- If a pending DTC is output, the system is malfunctioning.
- If a pending DTC is not output, perform the following procedure.

12. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.

13. Input the DTC: P050B.

14. Check the DTC judgment result.





HINT
- If the judgment result shows NORMAL, the system is normal.
- If the judgment result shows ABNORMAL, the system has a malfunction.
- If the judgment result shows INCOMPLETE or N/A, idle the engine for 3 minutes, let the engine cool down, and then perform steps [A] through [C] again.

15. If no pending DTC is output, perform a universal trip and check for permanent DTCs Reading and Clearing Diagnostic Trouble Codes.

HINT
- If a permanent DTC is output, the system is malfunctioning.
- If no permanent DTC is output, the system is normal.

INSPECTION PROCEDURE

HINT
- DTC P050B may be stored when the engine has the symptoms listed below. If necessary, check the trouble areas listed below.






- 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 be helpful in determining whether the vehicle was moving or stationary, whether the engine was warmed up or not, whether the air-fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.

PROCEDURE

1. CHECK FOR ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P050B)

(a) Connect the Techstream to the DLC3.

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

(c) Turn the Techstream on.

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

(e) Read the DTCs.

Result





HINT
If any DTCs other than P050B are output, troubleshoot those DTCs first.

B -- GO TO DTC CHART SFI System
A -- Continue to next step.

2. READ VALUE USING TECHSTREAM (FUEL TRIM)

HINT
Calculate the total fuel trim values to check the characteristic deviation of the mass air flow meter.

(a) Connect the Techstream to the DLC3.

(b) Start the engine and warm it up.

(c) Turn the Techstream on.

(d) Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Short FT #1 and Long FT #1, or Short FT #2 and Long FT #2.

(e) Read the values displayed on the Techstream.

(f) Add together the Short FT #1 and Long FT #1, or Short FT #2 and Long FT #2 values to obtain the total fuel trim.

OK:

Total of Short FT #1 and Long FT #1, or Short FT #2 and Long FT #2 values is between -20% and 20%.

NG -- CHECK PCV HOSE
OK -- Continue to next step.

3. INSPECT THROTTLE BODY ASSEMBLY

(a) Check for deposits around the throttle valve and check the throttle valve condition.

OK:

No deposits around throttle valve and throttle valve moves smoothly.

NG -- REPAIR OR REPLACE THROTTLE BODY ASSEMBLY
OK -- Continue to next step.

4. 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 that Throttle Idle Position is ON and check the engine idling condition and the value of MAP 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:





OK -- CHECK WHETHER DTC OUTPUT RECURS

NG -- INSPECT EGR VALVE ASSEMBLY

5. INSPECT EGR VALVE ASSEMBLY

(a) Remove the EGR valve assembly Removal.

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

OK:

EGR valve is tightly closed.

OK -- CHECK WHETHER DTC OUTPUT RECURS

NG -- REPLACE EGR VALVE ASSEMBLY

6. REPAIR OR REPLACE THROTTLE BODY ASSEMBLY

(a) Repair or replace the throttle body assembly Removal.

NEXT -- CHECK WHETHER DTC OUTPUT RECURS

7. CHECK PCV HOSE

(a) Check the PCV hose connections Testing and Inspection.

OK:

PCV hose is connected correctly and is not damaged.

NG -- REPAIR OR REPLACE PCV HOSE
OK -- Continue to next step.

8. CHECK AIR INDUCTION SYSTEM

(a) Check the air induction system for vacuum leaks Intake System.

OK:

No leak in the air induction system.

NG -- REPAIR OR REPLACE AIR INDUCTION SYSTEM
OK -- Continue to next step.

9. INSPECT AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY

(a) Visually check that the air cleaner filter element is not excessively contaminated with dirt or oil.

OK:

The air cleaner filter element is not excessively contaminated with dirt or oil.

NG -- REPLACE AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY
OK -- Continue to next step.

10. 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 that Throttle Idle Position is ON and check the engine idling condition and the value of MAP 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:





OK -- PERFORM ACTIVE TEST USING TECHSTREAM (CONTROL THE VVT SYSTEM)

NG -- INSPECT EGR VALVE ASSEMBLY

11. INSPECT EGR VALVE ASSEMBLY

(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 ASSEMBLY
OK -- Continue to next step.

12. PERFORM ACTIVE TEST USING TECHSTREAM (CONTROL THE VVT SYSTEM)

(a) Connect the Techstream to the DLC3.

(b) Start the engine.

(c) Turn the Techstream on.

(d) Warm up the engine.

(e) Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the VVT System (Bank 1) or Control the VVT System (Bank 2).

(f) Check the engine speed while operating the camshaft timing oil control valve using the Techstream.

OK:





NG -- CHECK AND REPAIR VVT SYSTEM
OK -- Continue to next step.

13. READ VALUE USING TECHSTREAM (MAF)

(a) Connect the Techstream to the DLC3.

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

(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 (167°F) or higher.

(f) Read MAF with the engine speed at 3000 rpm.

Standard:

Between 18.3 gm/s. and 25.8 gm/s. (shift lever: N; A/C: Off).

OK -- CHECK WHETHER DTC OUTPUT RECURS

NG -- CHECK HARNESS AND CONNECTOR

14. REPAIR OR REPLACE PCV HOSE

(a) Repair or replace the PCV hose.

NEXT -- CHECK WHETHER DTC OUTPUT RECURS

15. REPAIR OR REPLACE AIR INDUCTION SYSTEM

(a) Repair or replace the air induction system.

NEXT -- CHECK WHETHER DTC OUTPUT RECURS

16. REPLACE AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY

(a) Replace the air cleaner filter element sub-assembly.

NEXT -- CHECK WHETHER DTC OUTPUT RECURS

17. REPLACE EGR VALVE ASSEMBLY

(a) Replace the EGR valve assembly Removal.

NEXT -- CHECK WHETHER DTC OUTPUT RECURS

18. CHECK AND REPAIR VVT SYSTEM

(a) Check and repair the VVT system.

NEXT -- Continue to next step.

19. CHECK WHETHER DTC OUTPUT RECURS

NOTICE:
In this operation, the engine must be cold (approximately the same as the engine coolant temperature recorded in the freeze frame data).

(a) Connect the Techstream to the DLC3.

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

(c) Turn the Techstream on.

(d) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.

(e) Turn the engine switch off.

(f) Turn the engine switch on (IG) and turn the Techstream on.

(g) Enter the following menus: Powertrain / Engine and ECT / Data List / Coolant Temp.

(h) Check that the engine coolant temperature is between -10°C and 50°C (14 and 122°F)

(i) Start the engine and warm it up.

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

(k) Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.

(l) Input the DTC: P050B.

(m) Check the DTC judgment result.

Result





B -- CHECK HARNESS AND CONNECTOR

A -- CHECK FOR INTERMITTENT PROBLEMS Check for Intermittent Problems

20. CHECK HARNESS AND CONNECTOR

(a) Check the connection and terminal contact pressure of connectors and wire harnesses between the mass air flow meter and ECM Electronic Circuit Inspection Procedure.

HINT
Repair any problems.

NEXT -- Continue to next step.

21. CHECK WHETHER DTC OUTPUT RECURS

NOTICE:
In this operation, the engine must be cold (approximately the same as the engine coolant temperature recorded in the freeze frame data).

(a) Connect the Techstream to the DLC3.

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

(c) Turn the Techstream on.

(d) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.

(e) Turn the engine switch off.

(f) Turn the engine switch on (IG) and turn the Techstream on.

(g) Enter the following menus: Powertrain / Engine and ECT / Data List / Coolant Temp.

(h) Check that the engine coolant temperature is between -10°C and 50°C (14 and 122°F)

(i) Start the engine and warm it up.

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

(k) Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.

(l) Input the DTC: P050B.

(m) Check the DTC judgment result.

Result





B -- END
A -- Continue to next step.

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

(a) Disconnect the mass air flow 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.

23. REPLACE MASS AIR FLOW METER ASSEMBLY

(a) Replace the mass air flow meter assembly Removal.

HINT
If the result of the inspection performed in step 13 indicated no problem, proceed to the next step without replacing the mass air flow meter assembly.

NEXT -- Continue to next step.

24. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

NOTICE:
In this operation, the engine must be cold (approximately the same as the engine coolant temperature recorded in the freeze frame data).

(a) Connect the Techstream to the DLC3.

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

(c) Turn the Techstream on.

(d) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.

(e) Turn the engine switch off.

(f) Turn the engine switch on (IG) and turn the Techstream on.

(g) Enter the following menus: Powertrain / Engine and ECT / Data List / Coolant Temp.

(h) Check that the engine coolant temperature is between -10°C and 50°C (14 and 122°F).

(i) Start the engine and warm it up.

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

(k) Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.

(l) Input the DTC: P050B.

(m) Check the DTC judgment result.

Result





B -- REPLACE ECM Removal

A -- END