P2192
DTC P2192 SYSTEM TOO RICH AT HIGHER LOAD (BANK 1)Component Location:
GENERAL DESCRIPTION
In order to provide the best possible combination of driveablity, fuel economy and emission control, the PCM uses a closed loop air/fuel metering system. The PCM monitors the HO2S signal voltage and adjusts fuel delivery based it in closed loop fuel control. Changes in fuel delivery will be indicated by the long4erm and the short-term fuel trim values. The ideal fuel trim value is around 0%. The PCM will add fuel when the HO2S signal is indicating a lean condition. Additional fuel is indicated by fuel trim values that are above 0%. The PCM will reduce fuel when the HO2S signal is indicating a rich condition. Reduction in fuel is indicated by fuel trim values that are below 0%. The DTC relevant to fuel trim will be set when the amount reaches excessive levels because of a lean or rich condition.
DTC DESCRIPTION
Breaking the lambda adaptation and lambda controller limits for a long time, which may have been caused by failures in the fuel or intake system will involve emission rise and therefore shall be diagnosed by fuel system monitoring. The lambda controller deviation including adaptive terms are used for fuel system monitoring. The time counter is increased if lambda controller exceeds the threshold and the PCM sets DTC P2191 or P2192 respectively depending on direction of lambda controller deviation. P2191 is set with positive deviation and P2192 is set with negative deviation. If error code is set in the next driving cycle, the PCM illuminates the MIL.
DTC Detecting Condition:
Specification:
SIGNAL WAVEFORM & DATA
This figures show the wave form measured at terminal 2 of HO2S at idle
1. The average voltage of HO2S should be 0.5 V.
2. The HO2S voltage at point 0 is lean air/fuel duration and its usual voltage is below 0.2 V.
3. The HO2S voltage at point 02 is rich air/fuel duration and its usual voltage is over 0.7 V.
4. In case the duration 0 is longer than the duration (2)
Possible cause: Closed injector,low fuel pressure faulty MAPS, air leakage in intake system
5. In case the duration (2) is longer than the duration 0
Possible cause: Injector leakage, high fuel pressure, faulty MAP sensor faulty ECTS.
MONITOR DTC STATUS
This is the inspection procedure to determine whether it is present DTC or memoried one by monitoring the current signal or by using the function of oscilloscope with Hi-scan pro.
1. Connect scantool to Data Link Connector(DLC).
2. Warm up the engine to normal operating temperature.
3. Monitor the "FR HO2S signal" parameter on the scantool.
Service standard For front HO2S
- when decelerating suddenly from 4000 rpm: 200 mV or less
- When engine is suddenly raced 600 - 1000 mV
- 1500 rpm : The fluctuation between 400 mV or less and 600 - 1000 mV
4. Is parameter displayed within specifications?
YES: Fault is intermittent caused by poor contact in the sensor's and/or PCM's connector or was repaired and PCM memory was not cleared. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and then go to "Verification of Vehicle Repair" procedure
NO: Go to "W/Harness Inspection" procedure
TERMINAL & CONNECTOR INSPECTION
1. Many malfunctions in the electrical system are caused by poor harness and terminals. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
2. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage
3. Has a problem been found?
YES: Repair as necessary and go to "Verification of vehicle Repair" procedure.
NO: Go to "System inspection" procedure.
SYSTEM INSPECTION
1. Check for fuel pressure
1. Reduce the internal pressure of the fuel pipe and hoses and cover the hose connection with a shop towel to prevent splashing of fuel.
2. Remove the bolt connecting the fuel line to the fuel delivery pipe.
3. Using the fuel pressure gauge adaptor, install the fuel pressure gauge to the fuel pressure gauge adaptor.
4. Apply battery voltage to the terminal for he pump drive and activate the fuel pump: then, with fuel pressure applied,check fuel leakage from the pressure gauge or connection part.
5. Start an engine and warm up to operating temperature.
6. Check for fuel pressure at idle.
Specification : Fuel pressure at idle: 51 psi(350 kPa , 3.5 kg/sq.cm)
7. Is fuel pressure within specification?
YES: Go to "Check for Exhaust system " as below.
NO:
- Check fuel delivery system.
- Repair as necessary and then go to "Verification of Vehicle Repair" procedure.
2. Check for Exhaust system
1. Check exhaust system for leaks, cracks, loose connection. (especially exhaust manifold, catalyst around rear HO2S, etc.)
2. Is exhaust system okay?
YES: Go to "Check for Intake system"as below.
NO: Repair as necessary and then go to "Verification of Vehicle Repair" procedure.
3. Check for Intake system
Check intake system for leaks, cracks, loose connection as following items:
1. Throttle body gasket.
2. Gasket between intake manifold and surge tank.
3. Seals between intake manifold and fuel injectors.
4. Seals between surge tank and PCV valves..
5. Is intake system OK?
YES: Go to "Component Inspection" procedure.
NO: Repair as necessary and then go to "Verification of Vehicle Repair" procedure.
COMPONENT INSPECTION
1. Check for vacuum and PCV
Check for any split, disconnected or perforated vacuum hoses. Also, check PCV valve for proper operation.
1. Remove the positive crankcase ventilation valve.
2. Insert a thin stick into the positive crankcase ventilation valve from the threaded side to check that the plunger moves.
3. If the plunger does not move,the positive crankcase ventilation valve is clogged. Clean or replace It.
4. Are vacuum hoses and PCV OK?
YES: Go to "Check for Fuel injector" as below.
NO: Replace faulty vacuum hoses or PCV.
Repair as necessary and then go to "Verification of Vehicle Repair" procedure.
2. Check for Fuel injector
1. Check for fuel injector operation.
2. Are fuel injectors working normal and dispensing proper volume?
YES: Substitute with a known-good PCM and check for proper operation. If the problem is corrected, replace PCM and then go to "Verification of Vehicle Repair" procedure.
NO: Repair as necessary and then go to "Verification of Vehicle Repair" procedure.
VERIFICATION OF VEHICLE REPAIR
After a repair, it is essential to verify that the fault has been corrected.
1. Monitor and record the Freeze Frame Data for the Diagnostic Trouble Code (DTC) which has been diagnosed.
2. Using a Scantool, Clear the DTCs.
3. Operate the vehicle within conditions noted in the freeze frame data or enable conditions.
4. Monitor that all rediness test have been verified as "Complete"
5. Are any DTCs present?
YES: Go to the applicable troubleshooting procedure.
NO: System is performing to specification at this time.