P050B

2ZR-FE ENGINE CONTROL SYSTEM: SFI SYSTEM: P050B: Cold Start Ignition Timing Performance

DTC 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 set 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 lower than 50°C (122°F), the ECM checks the ignition timing at 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 set when the malfunction is detected in consecutive driving cycles (2 tip detection logic).
NOTE: When the negative battery terminal is disconnected during inspections or repairs, the ISC (Idle Speed Control) learning values are cleared. This DTC cannot be set with the ISC learning values cleared.
HINT: The ISC learning is performed when the engine is warmed up and has been idling for 5 minutes.









MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS





TYPICAL MALFUNCTION THRESHOLDS





INSPECTION PROCEDURE
HINT:
- DTC P050B may be set 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 running or stopped, 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 ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P050B)
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the tester ON.
(d) Select the following menu items: Powertrain / Engine and ECT / Trouble Codes.
(e) Read the DTCs.
Result:





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

NG -- GO TO DTC CHART
OK -- 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) Turn the ignition switch to ON.
(c) Turn the tester ON.
(d) Select the following menu items: Powertrain / Engine and ECT / Data List / A/F Control System / Short FT #1 and Long FT #1.
(e) Read the values displayed on the tester.
(f) Add together the Short FT #1 and Long FT #1 values to obtain the total Fuel Trim
OK:
Total of Short FT #1 and Long FT #1 values is between -20% and 20%.
NG -- PERFORM ACTIVE TEST USING TECHSTREAM (OCV OPERATION)
OK -- Continue to next step.
3. CHECK THROTTLE BODY
(a) Check that there are no deposits around the throttle valve.
OK:
No deposits around the throttle valve
NG -- REPAIR OR REPLACE THROTTLE BODY
OK -- Continue to next step.
4. REPLACE ECM
(a) Replace ECM Removal.
NEXT -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050B)
5. PERFORM ACTIVE TEST USING TECHSTREAM (OCV OPERATION)
(a) Connect the Techstream to the DLC3.
(b) Start the engine.
(c) Turn the tester ON.
(d) Turn the air conditioning switch to ON.
(e) Select the following menu items: Powertrain / Engine and ECT / Active Test / Control the VVT System (Bank 1).
(f) Check the engine speed while operating the OCV using the tester.
Result:





HINT: If the result is not acceptable, cool the engine and perform the Active Test again.
(g) Start the engine when the engine coolant temperature is 30 °C or less.
(h) Turn the tester ON.
(i) Turn the air conditioning switch to ON.
(j) Select the following menu items: Powertrain / Engine and ECT / Active Test / Control the VVT System (Bank 1).
(k) Check the engine speed while operating the OCV using the tester with the engine coolant temperature is 50 °C or less.
Result:






NG -- CHECK AND REPAIR VVT SYSTEM
OK -- Continue to next step.
6. CHECK PCV SYSTEM
(a) Start the engine.
(b) Pinch the positive crankcase ventilation (PCV) hose.
(c) Check the engine rpm.
OK:
The engine rpm rises when the PCV hose is pinched.
NG -- REPAIR OR REPLACE PCV SYSTEM
OK -- Continue to next step.
7. CHECK 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.
8. CHECK AIR INDUCTION SYSTEM
(a) Check the air induction system for vacuum leaks Testing and Inspection.
OK:
No leakage from the air induction system.
NG -- REPAIR OR REPLACE AIR INDUCTION SYSTEM
OK -- Continue to next step.
9. REPLACE MASS AIR FLOW METER
(a) Replace the mass air flow meter Removal.
NEXT -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050B)
10. REPAIR OR REPLACE THROTTLE BODY
(a) Repair or replace throttle body Removal.
NEXT -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050B)
11. CHECK AND REPAIR VVT SYSTEM
NEXT -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050B)
12. REPAIR OR REPLACE PCV SYSTEM
NEXT -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050B)
13. REPLACE AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY
NEXT -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050B)
14. REPAIR OR REPLACE AIR INDUCTION SYSTEM
NEXT -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050B)
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).
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the tester ON.
(d) Clear the DTCs DTC Check / Clear.
(e) Switch the ECM from normal mode to check mode using the tester Check Mode Procedure.
(f) Start the engine and idle it for one minute.
OK:
Stable fast idle
(g) Read the DTCs.
OK:
No DTC is output.
NEXT -- END