Inspection Procedure
HINT:
- DTC P050B may be set when the engine has the symptoms listed below. If necessary, check the trouble areas listed below.SYMPTOM CHART
Symptom 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 record 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.
- CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P050B)
- Connect a Techstream to the DLC3.
- Turn the ignition switch to ON.
- Turn the Techstream on.
- Enter the following menus: Powertrain/Engine and ECT/Trouble Codes.
- Read the DTCs.
Result
RESULT REFERENCEResult Proceed To P050B A P050B and other DTCs B HINT:
If any DTCs other than P050B are output, troubleshoot those DTCs first.
NG: GO TO DTC CHART
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 a Techstream to the DLC3.
- Turn the ignition switch to ON.
- 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
Standard:
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
- INSPECT THROTTLE WITH MOTOR BODY ASSEMBLY
- 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
- Check that there are no deposits around the throttle valve.
- REPLACE ECM
- PERFORM ACTIVE TEST USING TECHSTREAM (OCV OPERATION)
- Connect a Techstream to the DLC3.
- Start the engine and turn the Techstream on.
- Warm up the engine.
- Enter the following menus: Powertrain/Engine and ECT/Active Test/Control the VVT System (Bank 1) or Control the VVT System (Bank 2).
- Check the engine speed while operating the Oil Control Valve (OCV) using the Techstream.
OK
OIL CONTROL VALVE OPERATION CHARTTester Operation Specified Condition OCV OFF Normal engine speed OCV ON Engine Idles roughly or stalls (soon after OCV switched from OFF to ON) NG: Go to step 11
OK: Go to Next Step
- CHECK PCV SYSTEM
- Start the engine.
- Pinch the positive crankcase PCV hose.
- Check the engine rpm.
OK:
The engine rpm rises when the PCV hose is pinched.
NG: Go to step 12
OK: Go to Next Step
- INSPECT AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY
- 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
- Visually check that the air cleaner filter element is not excessively contaminated with dirt or oil.
- CHECK AIR INDUCTION SYSTEM
- Check the air induction system for vacuum leaks.
OK:
No leak from the air induction system.
NG: Go to step 14
OK: Go to Next Step
- Check the air induction system for vacuum leaks.
- REPLACE MASS AIR FLOW METER
- Replace the mass air flow meter (See MASS AIR FLOW METER
).
NEXT: Go to step 15
- Replace the mass air flow meter (See MASS AIR FLOW METER
).
- REPAIR OR REPLACE THROTTLE WITH MOTOR BODY ASSEMBLY
- Repair or replace throttle with motor body assembly (See ON-VEHICLE INSPECTION
).
NEXT: Go to step 15
- Repair or replace throttle with motor body assembly (See ON-VEHICLE INSPECTION
).
- CHECK AND REPAIR VVT SYSTEM
NEXT: Go to step 15
- REPAIR OR REPLACE PCV SYSTEM
NEXT: Go to step 15
- REPLACE AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY
NEXT: Go to step 15
- REPAIR OR REPLACE AIR INDUCTION SYSTEM
NEXT: Go to step 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).
- Connect a Techstream to the DLC3.
- Turn the ignition switch to ON.
- Turn the Techstream on.
- Clear the DTCs (See DTC CHECK/CLEAR ).
- Switch the ECM from normal mode to check mode using the Techstream (See CHECK MODE PROCEDURE ).
- Start the engine and idle it for one minute.
OK:
Stable fast idle
- Read the DTCs.
OK:
No DTC is output.
NEXT: END