Inspection Procedure

HINT:

• DTC P050B may be stored when the engine has the symptoms listed below. If necessary, check the trouble areas listed below.
  PROBLEM SYMPTOM CHART
  
  

  Symptoms	Factor	Trouble Area
  Low idle speed when engine is cold (immediately after engine start)	Excessive engine friction	Engine oil deterioration Drive belt tension A/C compressor Generator P/S pump
  Rough idle when engine is cold (immediately after engine start)	Abnormal combustion	Fuel quality

• 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.

1. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P050B) 
   1. Connect the Techstream to the DLC3.
   2. Turn the engine switch on (IG).
   3. Turn the Techstream on.
   4. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
   5. Read the DTCs.

      Result 

   RESULT REFERENCE
   
   

   Result	Proceed to
   P050B	A
   P050B and other DTCs	B

   HINT:

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

   B: GO TO DTC CHART  (See DIAGNOSTIC TROUBLE CODE CHART )

   A: Go 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.

   1. Connect the Techstream to the DLC3.
   2. Turn the engine switch on (IG).
   3. Turn the Techstream on.
   4. Enter the following menus: Powertrain / Engine and ECT / Data List / A/F Control System / Short FT #1 and Long FT #1, or Short FT #2 and Long FT #2.
   5. Read the values displayed on the Techstream.
   6. 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:  Go to step  5

      OK: Go to next step 

3. CHECK THROTTLE BODY 
   1. Check that there are no deposits around the throttle valve.

      OK: No deposits around the throttle valve. 

      NG:  Go to step  10

      OK: Go to next step 

4. REPLACE ECM 
   1. Replace the ECM (See ECM ).

      NEXT:  Go to step  15

5. PERFORM ACTIVE TEST USING TECHSTREAM (OCV OPERATION) 
   1. Connect the Techstream to the DLC3.
   2. Start the engine and turn the Techstream on.
   3. Warm up the engine.
   4. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the VVT System (Bank 1) or Control the VVT System (Bank 2).
   5. Check the engine speed while operating the Oil Control Valve (OCV) using the Techstream.

   OK 

   ACTIVE TEST
   
   

   Operation	Specified Condition
   OCV OFF	Normal engine speed
   OCV ON	Soon after OCV switched from OFF to ON, engine idles roughly or stalls

   NG:  Go to step  11

   OK: Go to next step 

6. CHECK PCV SYSTEM 
   1. Start the engine.
   2. Pinch the PCV hose.
   3. Check the engine speed.

      OK: The engine speed rises when the PCV hose is pinched. 

   NG:  Go to step  12

   OK: Go to next step 

7. CHECK AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY 
   1. 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:  Go to step  13

   OK: Go to next step 

8. CHECK AIR INDUCTION SYSTEM 
   1. Check the air induction system for vacuum leaks (See ON-VEHICLE INSPECTION ).

      OK: No leakage from the air induction system. 

   NG:  Go to step  14

   OK: Go to next step 

9. REPLACE MASS AIR FLOW METER 
   1. Replace the mass air flow meter (See REMOVAL ).

   NEXT:  Go to step  15

10. REPAIR OR REPLACE THROTTLE BODY 
    1. Repair or replace the throttle body (See REMOVAL ).

    NEXT:  Go to step  15

11. CHECK AND REPAIR VVT SYSTEM 

    NEXT:  Go to step  15

12. REPAIR OR REPLACE PCV SYSTEM 

    NEXT:  Go to step  15

13. REPLACE AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY 

    NEXT:  Go to step  15

14. REPAIR OR REPLACE AIR INDUCTION SYSTEM 
15. CHECK WHETHER DTC OUTPUT RECURS (DTC P050B) 
    NOTE: For this operation, the engine must be cold (the same level as the engine coolant temperature recorded in the freeze frame data).
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Clear the DTCs (See DTC CHECK/CLEAR ).
    5. Switch the ECM from normal mode to check mode using the Techstream (See CHECK MODE PROCEDURE ).
    6. Start the engine and idle it for one minute.
    7. Check that the idling is stable and fast.

       OK: Stable fast idle 

    8. Read the DTCs.

       OK: No DTC is output. 

       NEXT: END