DTC P050A: Cold Start Idle Air Control System Performance: Procedure
- CHECK DTCS
OK
Any other DTCs are not output.
NG → See step 16
OK: Go to next step
- READ VALUE USING TECHSTREAM (FUEL TRIM)
HINT:
Calculate the total fuel trim values to check the characteristic deviation of the mass air flow meter.
- Connect the Techstream to the DLC3.
- Turn the engine switch on (IG) and turn the Techstream on.
- 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.
- Read the values displayed on the Techstream.
- 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.
Result
Total of Short FT #1 and Long FT #1, or Short FT #2 and Long FT #2 values is between -20% and 20%.
NG → See step 4
OK: Go to next step
- CHECK THROTTLE BODY
- Check for deposits around the throttle valve and throttle valve condition.
OK
No deposits around throttle valve and throttle valve moves smoothly.
OK → See step 9
NG → See step 8
- Check for deposits around the throttle valve and throttle valve condition.
- CHECK VVT SYSTEM
- Allow the engine to idle after the engine is warmed up.
- Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the VVT System (Bank 1) or Control the VVT System (Bank 2).
- Turn on Control the VVT System (Bank 1) or Control the VVT System (Bank 2) to advance the valve timing.
- Check the engine condition.
OK
The engine stalls or idles roughly when Control the VVT System is ON (VVT system is OK).
NG → See step 10
OK: Go to next step
- CHECK PCV SYSTEM
- Allow the engine to idle.
- Pinch the positive crankcase ventilation (PCV) hose.
- Check the engine speed.
OK
The engine speed rises when the PCV hose is pinched.
NG → See step 11
OK: Go to next step
- CHECK AIR CLEANER FILTER
- Visually check that the air cleaner filter is not excessively contaminated with dirt or oil.
NG → See step 12
OK: Go to next step
- CHECK AIR INDUCTION SYSTEM
- Check the air induction system for vacuum leakage. Refer to ON-VEHICLE INSPECTION - Step 4 .
OK → See step 14
NG → See step 13
- REPAIR OR REPLACE THROTTLE BODY
- Repair or replace the throttle body. Refer to REMOVAL .
NEXT → See step 15
- REPLACE ECM
- Replace the ECM. Refer to REMOVAL .
NEXT → See step 15
- CHECK AND REPAIR VVT SYSTEM
NEXT → See step 15
- REPAIR OR REPLACE PCV HOSE
NEXT → See step 15
- REPLACE AIR CLEANER FILTER
NEXT → See step 15
- REPAIR OR REPLACE AIR INDUCTION SYSTEM
NEXT → See step 15
- REPLACE MASS AIR FLOW METER
- Replace the mass air flow meter. Refer to REMOVAL .
NEXT: Go to next step
- CHECK DTCS
- Check that the engine coolant temperature is -10 to 50°C (14 to 122°F).
- Clear the DTC. Refer to DTC CHECK / CLEAR .
- Enter the check mode using the Techstream. Refer to CHECK MODE PROCEDURE .
- Allow the engine to idle for 1 minute.
- Check that no DTC is output.
NEXT → END
- GO TO DIAGNOSTIC TROUBLE CODE CHART. Refer to DIAGNOSTIC TROUBLE CODE CHART