DTC P2097


DTC P2097	Target A/F feedback system too rich
DETECTION CONDITION	• The PCM monitors the target A/F fuel trim when under the target A/F feedback control. If the fuel trim is less than the specification, the PCM determines that the target A/F feedback system is too rich. Diagnostic support note • This is a continuous monitor (Fuel system). • The MIL illuminates if the PCM detects the above malfunction condition in two consecutive drive cycles or in one drive cycle while the DTC for the same malfunction has been stored in the PCM. • PENDING CODE is available if the PCM detects the above malfunction condition during first drive cycle. • FREEZE FRAME DATA is available. • The DTC is stored in the PCM memory.
POSSIBLE CAUSE	• Leakage exhaust gas • Rear HO2S malfunction • IAT sensor malfunction • ECT sensor malfunction • Front HO2S malfunction • Fuel pump speed control malfunction • Fuel line pressure malfunction • Fuel pump unit malfunction • Purge solenoid valve malfunction • Insufficient compression – Metering oil pump malfunction – Engine oil condition malfunction – Rised oil pressure – Oil passage malfunction – Engine malfunction • PCM malfunction


STEP	INSPECTION		ACTION
1	VERIFY FREEZE FRAME DATA HAS BEEN RECORDED • Has FREEZE FRAME DATA been recorded?	Yes	Go to the next step.
1		No	Record the FREEZE FRAME DATA on the repair order, then go to the next step.
2	VERIFY RELATED REPAIR INFORMATION AVAILABILITY • Verify related service repair information availability. • Is any related repair information available?	Yes	Perform repair or diagnosis according to the available repair information. • If the vehicle is not repaired, go to the next step.
2		No	Go to the next step.
3	VERIFY RELATED PENDING CODE OR STORED DTC • Turn the ignition switch off, then to the ON position (Engine off). • Verify the related PENDING CODE or stored DTCs. • Is the DTC P0172 also present?	Yes	Go to the DTC P0172 inspection. (See DTC P0172.)
3		No	If misfire DTC is present or drivability concern exists, go to step 11. If misfire DTC is not present and drivability concern does not exist, go to the next step.
4	IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA • Is DTC P2097 on FREEZE FRAME DATA?	Yes	Go to the next step.
4		No	Go to the FREEZE FRAME DATA DTC inspection. (See DTC TABLE.)
5	VERIFY CURRENT INPUT SIGNAL STATUS OF REAR HO2S • Connect the WDS or equivalent to the DLC-2. • Start the engine and warm it up completely. • Access the O2S12 PID. • Read the O2S12 PID under following accelerator pedal condition (in PARK or NEUTRAL). – More than 0.55 V when accelerator pedal is suddenly depressed (rich condition). – Less than 0.55 V just after release of accelerator pedal (lean condition) • Is the PID normal?	Yes	Go to the next step.
5		No	Visually inspect for the the gas leakage between TWC and rear HO2S. • If there is no leakage, replace the rear HO2S. (See REAR HEATED OXYGEN SENSOR (HO2S) REMOVAL/INSTALLATION.) Then go to Step 17.
6	VERIFY CURRENT INPUT SIGNAL STATUS • Connect the WDS or equivalent to the DLC-2. • Verify the following PIDs. (See PCM INSPECTION.) – APP – ECT – MAF – TP – VSS • Are the PIDs normal?	Yes	Go to the next step.
6		No	Inspect the malfunctioning part according to the inspection results. Then go to Step 17.
7	VERIFY CURRENT INPUT SIGNAL STATUS UNDER FREEZE FRAME DATA CONDITION • Connect the WDS or equivalent to the DLC-2. • Verify the following PIDs under the FREEZE FRAME DATA condition. (See PCM INSPECTION.) – APP – ECT – MAF – TP – VSS • Are the PIDs normal?	Yes	Go to the next step.
7		No	Inspect the malfunctioning part according to the inspection results. Then go to Step 17.
8	VERIFY CURRENT INPUT SIGNAL STATUS OF FRONT HO2S • Connect the WDS or equivalent to the DLC-2. • Start the engine and warm it up completely. • Access the O2S11 PID. • Read the O2S11 PID under following accelerator pedal condition (in PARK or NEUTRAL). – Less than 1 mA when accelerator pedal is suddenly depressed (rich condition). – More than 1 mA just after release of accelerator pedal (lean condition) • Is the PID normal?	Yes	Go to the next step.
8		No	Replace the front HO2S. (See FRONT HEATED OXYGEN SENSOR (HO2S) REMOVAL/INSTALLATION.) Then go to Step 17.
9	INSPECT FUEL PUMP SPEED CONTROL OPERATION • Perform the "Fuel Pump Speed Control Operation Inspection". (See Fuel Pump Speed Control Operation Inspection.) • Is there any malfunction?	Yes	Repair or replace the malfunctioning part according to the inspection results. Then go to Step 17.
9		No	Go to the next step.
10	INSPECT FUEL LINE PRESSURE • Perform the "FUEL LINE PRESSURE INSPECTION". (See FUEL LINE PRESSURE INSPECTION.) • Is there any malfunction?	Yes	• If the fuel line pressure is too low, go to the next step. • If the fuel line pressure is too high, replace the fuel pump unit, then go to Step 17. (See FUEL PUMP UNIT REMOVAL/INSTALLATION.)
10		No	Go to Step 13.
11	INSPECT LONG TERM FUEL TRIM • Connect the WDS or equivalent to the DLC-2. • Access the LONGFT1 PID. • Compare the LONGFT1 PID with recorded FREEZE FRAME DATA at Step 1. • Is the LONGFT1 PID above FREEZE FRAME DATA?	Yes	Inspect the purge solenoid valve. (See PURGE SOLENOID VALVE INSPECTION.) • If there is any malfunction, replace the purge solenoid valve. (See INTAKE-AIR SYSTEM HOSE ROUTING DIAGRAM.) Then go to Step 17.
11		No	Go to the next step.
12	INSPECT ENGINE COMPRESSION • Inspect the engine compression. (See COMPRESSION INSPECTION.) • Is there any malfunction?	Yes	Go to the next step.
12		No	Go to Step 17.
13	INSPECT METERING OIL PUMP • Inspect the metering oil pump. (See METERING OIL PUMP INSPECTION.) • Is there any malfunction?	Yes	Repair or replace the malfunctioning part according to the inspection results. Overhaul or replace the engine. Then go to Step 17.
13		No	Go to the next step.
14	INSPECT ENGINE OIL CONDITION • Inspect the engine oil condition. • Is the engine oil condition normal?	Yes	Go to the next step.
14		No	Replace the engine oil. Inspect the ECT sensor and related harnesses. (See ENGINE COOLANT TEMPERATURE (ECT) SENSOR INSPECTION.) Overhaul or replace the engine. Then go to Step 17.
15	INSPECT OIL PRESSURE • Inspect the oil pressure. (See OIL PRESSURE INSPECTION.) • Is there any malfunction?	Yes	Repair or replace the malfunctioning part according to the inspection results. Overhaul or replace the engine. Then go to Step 17.
15		No	Go to the next step.
16	INSPECT OIL PASSAGE • Inspect the oil pipe between metering oil pump and metering oil nozzle. • Is there any malfunction?	Yes	Inspect and repair for leakage and/or clogged in oil passage at engine. Overhaul or replace the engine. Then go to the next step.
16		No	Overhaul or replace the engine. Then go to the next step.
17	VERIFY TROUBLESHOOTING OF DTC P2097 COMPLETED • Make sure to reconnect all disconnected connectors. • Clear the DTC from the PCM memory using the WDS or equivalent. • Perform the "DRIVE MODE 1". (See OBD DRIVE MODE.) • Is the PENDING CODE same as DTC present?	Yes	Replace the PCM, then go to the next step. (See PCM REMOVAL/INSTALLATION.)
17		No	Go to the next step.
18	VERIFY AFTER REPAIR PROCEDURE • Perform the "AFTER REPAIR PROCEDURE". (See AFTER REPAIR PROCEDURE.) • Are any DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE.)
18		No	DTC troubleshooting completed.