Inspection Procedure

HINT:

DTC P050B may be set when the engine has the symptoms listed below. If necessary, check the trouble area listed below.

1. CHECK DTCS 

   Result: 

   Any other DTCs are not set. 

   NG: GO TO DIAGNOSTIC TROUBLE CODE CHART 

   OK: Go to next step 

2. READ SHORT-TERM AND LONG-TERM FUEL TRIMS 

   HINT:

   The total of the short-term fuel trim (SHORT FT) and long-term fuel trim (LONG FT) is used to discover a problem in the induction system (between air cleaner and intake manifold).

   1. Allow the engine to idle.
   2. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / DATA LIST / PRIMARY.
   3. Read the value of SHORT FT #1 and LONG FT #1 (bank 1).
   4. Read the value of SHORT FT #2 and LONG FT #2 (bank 2).

      Result: 

      Total of SHORT FT and LONG FT is between -20% and 20% 

   NG: Go to step  4

   OK: Go to next step 

3. CHECK THROTTLE BODY 
   1. Check for deposits around the throttle valve and throttle valve condition.

      Result: 

      No deposits around throttle valve and throttle valve moves smoothly. 

   NG: Go to step  8

   OK: Go to step  9

4. CHECK VVT SYSTEM 
   1. Allow the engine to idle with the engine warmed up.
   2. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST / VVT CTRL B1 (or VVT CTRL B2).
   3. Turn on VVT CTRL B1 (or VVT CTRL B2) to advance the valve timing.
   4. Check the engine condition.

      Result: 

      The engine stalls or idles roughly when VVT CTRL is ON. (VVT system is OK) 

   NG: Go to step  10

   OK: Go to next step 

5. CHECK PCV SYSTEM 
   1. Allow the engine to idle.
   2. Pinch the positive crankcase ventilation (PCV) hose.
   3. Check the engine rpm.

      Result: 

      The engine rpm rises when the PCV hose is pinched. 

   NG: Go to step  11

   OK: Go to next step 

6. CHECK AIR CLEANER FILTER 
   1. Visually check that the air cleaner filter is not excessively contaminated with dirt or oil.

   NG: Go to step  12

   OK: Go to next step 

7. CHECK AIR INDUCTION SYSTEM 
   1. Check the air induction system for vacuum leakage.

   NG: Go to step  13

   OK: Go to step  14

8. REPAIR OR REPLACE THROTTLE BODY 
9. REPLACE ECM 

   NEXT: Go to step  15

10. CHECK AND REPAIR VVT SYSTEM 

    NEXT: Go to step  15

11. REPAIR OR REPLACE PCV HOSE 

    NEXT: Go to step  15

12. REPLACE AIR CLEANER FILTER 

    NEXT: Go to step  15

13. REPAIR OR REPLACE AIR INDUCTION SYSTEM 

    NEXT: Go to step  15

14. REPLACE MASS AIR FLOW METER 

    NEXT: Go to step 15 

15. CHECK DTCS 
    1. Check that the engine coolant temperature is -10 to 50°C (14 to 122°F).
    2. Clear the DTC.
    3. Enter the check mode using the intelligent tester.
    4. Allow the engine to idle for 1 minute.
    5. Check that no DTC is present.

    NEXT: END