P2097 Fault Code

Long Description

Fault code P2097 is logged when the powertrain control module (PCM) has detected an issue with the air-fuel mixture in the exhaust system.

This occurs when the oxygen sensor that is downstream of the catalytic converter in bank 1 has signaled that the exhaust gases are too rich.

Engines run on an ideal fuel ratio of 14.7 parts of air to every 1 part of fuel. The term ‘rich’ is used to describe an engine that is running with too much fuel in the air-fuel mixture.

Exhaust gases are monitored to give the PCM information about how the combustion process is going. They also help to monitor emissions in the exhaust fumes.

Bank 1 refers to the side of the engine in which cylinder 1 is located. This applies only to V-shape engines.

Manufacturers like Jeep, Chevrolet, and Subaru are some of the more commonly searched when it comes to this P2097 fault code.

Other Signs of This Problem

Running rich can come with a number of symptoms. However, these are typically more subtle than an engine that is running with too little fuel, often referred to as running lean.

One of the most obvious signs of a problem is the presence of the Check Engine light.

A reduction in performance is another sign of this issue. It is possible for the engine to misfire, suffer reduced power, higher fuel consumption, and stall.

Be sure to look out for additional fault codes that indicate running rich or misfiring. These can be codes like P0172 or P0300 up to P0308.

These codes can help determine where the disruption in the ideal air-fuel mixture is occurring.

Depending on how rich the engine is running, it is possible for the tailpipes to emit black smoke or an odor of fuel as unburnt fuel is leaving the exhaust system.

What Could Be The Problem?

There are several potential causes for P2097. These relate to an engine that is actually running rich or a fault in the oxygen sensor circuit. It is also possible there is an issue with the exhaust system.

If the downstream oxygen sensor has failed or suffered a circuitry issue, it can provide a false reading to the PCM, triggering the fault code.

A leak in the exhaust system can also cause the fault code to be triggered. These can be found anywhere upstream of the oxygen sensor.

A failing catalytic converter can cause excess fuel to be detected in the exhaust gases. This happens as the component cannot properly reduce emissions.

Fixes

Fixes for this type of issue are dependent on whether the engine is actually running rich or if there is an issue in the exhaust system. It is also possible that the post-catalytic converter oxygen sensor circuit is faulty.

If the engine is running rich, the corresponding fault codes need to be fixed first.

If the oxygen sensor is faulty, it needs to be replaced. Additionally, the wiring and connections in the circuit must be repaired if there is any damage or looseness.

Any leaks in the exhaust system need to be fixed, particularly upstream of the oxygen sensor.

A failing or damaged catalytic converter needs to be repaired or replaced.

Seriousness

Fault code P2097 should be considered a moderately serious issue. In some instances, there will be no noticeable driveability issues present.

However, it is possible that prolonged driving in this state can cause damage to the catalytic converter, which can be expensive to fix.

It is a good idea to have the problem fixed as soon as possible.