DTC Advanced Diagnostics: P2097 (3.0L Engine)

DTC P2097: Post Catalyst Fuel Trim System Too Rich

General Description

Courtesy of HONDA, U.S.A., INC.

The feedback control of the secondary heated oxygen sensor (secondary HO2S (sensor 2)) can be done by monitoring the long term fuel trim value. If the learned value of the secondary HO2S (sensor 2) feedback is a specified value, the PCM detects a malfunction and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type

Execution	Continuous
Sequence	None
Duration	10 seconds or more
DTC Type	Two drive cycles, MIL on

Enable Conditions

Condition	Minimum	Maximum
MAF value [MAF Sensor]	10 g/s (0.36 oz/s)	-
Secondary HO2S (sensor 2) feedback	Closed loop

[ ]: HDS Parameter

Malfunction Threshold

The learned value of the secondary HO2S (sensor 2) feedback is +5.5 % or more for at least 10 seconds.

Possible Cause

NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.

Rear A/F sensor (bank 1, sensor 1) failure
Front A/F sensor (bank 2, sensor 1) failure
Secondary HO2S (sensor 2) failure
Catalyst failure
Fuel system failure
Intake air failure

Confirmation Procedure

Operating Condition

Start the engine.
Drive at a steady speed between 56 mph (90 km/h) with accelerator pedal pressed for 15 minutes or more.

When freeze data is stored, drive the vehicle under those conditions instead of Driving Pattern step 2.
Drive the vehicle in this manner only if the traffic regulations and ambient conditions allow.

Diagnosis Details

Conditions for setting the DTC

When a malfunction is detected during the first drive cycle, a Pending DTC is stored in the PCM memory. If the malfunction returns in the next (second) drive cycle, the MIL comes on and a Confirmed DTC, the freeze data, and the on-board snapshot are stored.

Conditions for clearing the DTC

The MIL is cleared if the malfunction does not return in three consecutive drive cycles in which the engine conditions are similar to the first time the malfunction was detected. The MIL, the Pending DTC, the Confirmed DTC, the freeze data, and the on-board snapshot can be cleared with the scan tool clear command.