P2098 Fuel Trim System After Catalyst Too Lean Bank 2

P2098 Fuel Trim System After Catalyst Too Lean Bank 2

OBD-II DTC Datasheet

Too Lean Fuel System After Catalyst, Bank 2

What does this mean?

This is a generic transmission code which means it covers all makes / models from 1996 onwards. However, specific troubleshooting steps may differ from vehicle to vehicle.

Code P2098, Post Catalyst Fuel Trim System Too Lean in Bank 2, is simply put into a lean state (too much air and not enough fuel), which the PCM has recognized from the signals from the oxygen sensors. Bank 2 refers to the side of the engine that does not contain cylinder # 1.

A number of oxygen sensors in the exhaust system constantly signal the ratio of fuel in the mixture. Every exhaust system with a catalytic converter will have two sensors - one between the engine and the converter and one after the converter.

Oxygen sensors signal to the engine management computer the amount of oxygen present in the exhaust, which is used to determine and control the fuel ratio. The higher the oxygen content, the leaner the fuel mixture, and vice versa, the richer the mixture. This occurs in the form of a series of impulses called "cross-counting". At the tip of the sensor is zirconium, which reacts to oxygen in such a way that it creates its own stress when hot. It needs to be around 250 degrees Fahrenheit to work and generate up to 0.8 volts.

During operation, the oxygen sensor will cycle once per second and supply the computer with a voltage ranging from 0.2 to 0.8 for a rich mixture. An ideal mixture will average signals around 0.45 volts. The target fuel to air ratio in the computer is 14.7:1. The oxygen sensor will not work at low temperatures such as startup - for this reason, most front sensors have a preheater to reduce their warm-up time.

Oxygen sensors have a dual task - to indicate unburned oxygen in the exhaust and, secondly, to indicate the health of the catalytic converter. The sensor on the engine side signals the mixture entering the converter, and the rear sensor signals the mixture leaving the converter.

When the sensors and transducer are working normally, the counter of the front sensor will be higher than that of the rear sensor, indicating a good transducer. When the front and rear sensors match, the front oxygen sensor is faulty, the converter is clogged, or another component is causing an erroneous oxygen sensor signal.

This code may or may not be less noticeable to the check engine light. It depends on the cause, however there is nothing that could fail on the vehicle without negatively affecting something else. Track the problem and fix the code as soon as possible to avoid damaging other components.

symptoms

The symptoms of a P2098 code will vary depending on the component or system causing the fuel trim malfunction. Not everyone will be present at the same time.

• Malfunction Indicator Lamp (MIL) illuminated with DTC P2098 set
• Rough idle
• Poor fuel economy
• Poor acceleration
• Misfire
• Cherry Red Hot Catalytic Converter
• Possible spark detonator (knock / premature ignition)
• Additional codes associated with P2098

Possible reasons

Reasons for this DTC may include:

• Low fuel pressure caused by clogged filter, fuel pump failure, fuel pressure regulator failure, or clogged or leaking injectors.
• Rough engine running due to spark plug misfires. Many engines have misfire codes to indicate which cylinder the failure occurred, such as P0307 for number 7.
• A large vacuum leak will force a large amount of unmetered air into the intake manifold, resulting in an excessively lean mixture.
• A large air leak at or near the number one oxygen sensor can also cause a lean mixture.
• A connected converter will cause a lot of drivability issues and will also install this code. A heavily clogged converter will make it impossible to increase rpm under load. Look for a code such as P0421 - Catalytic converter efficiency below threshold if the converter indicates a faulty converter.
• Defective oxygen sensor. This will set the code by itself, however a faulty oxygen sensor does not automatically disable the oxygen sensor. The code simply means that the sensor signal is out of specification. An air leak or any of the above will cause an erroneous signal. There are many O2 codes pertaining to O2 characteristics that indicate a problem area.
• The mass air flow sensor will also cause this problem. This will be accompanied by a code such as P0100 - Mass Air Flow Circuit Malfunction. The mass air flow sensor is a hot wire that detects the amount of air entering the intake manifold. The computer uses this information to control the fuel mixture.
• Rusty exhaust systems, cracked exhaust manifolds, damaged or missing gaskets, or donuts will cause air leaks.

To determine cause and effect for vehicles, consider this scenario. A simple air leak in front of the number one oxygen sensor will add extra air to the mixture, not measured by the computer. The oxygen sensor signals a lean mixture due to lack of air dosage.

Immediately, the computer enriches the mixture to prevent damage to the lean mixture due to detonation, among other factors. An excessively rich mixture starts to clog candles, contaminate oil, heat up the converter and reduce fuel consumption. These are just a few of the things that happen in these circumstances.

Diagnostic and repair procedures

It is advisable to go online and obtain Technical Service Bulletins (TSB) associated with these codes and descriptions. While all vehicles have the same cause, some may have a service history of problems with a specific component associated with that code.

If you have access to an advanced diagnostic scan tool like Tech II or Snap-On Vantage, it will save you a lot of time. The scanner can graph and display digital information about the performance of each sensor in real time. It will show the working oxygen sensors to easily recognize the faulty one.

Jeeps and some Chrysler products seem to suffer from poor electrical connectors, so check them carefully. In addition, Jeep has had several PCM upgrades on later models. Reprogramming upgrades as well as replacing the oxygen sensor for any reason are covered by an 8 years / 80,000 miles warranty. To check if the update is complete, look near or behind the battery and there will be a serial number with the date the computer was updated. If not already done, it is free for the specified period.

• Connect the code scanner to the OBD port under the dashboard. Turn the key to the "On" position with the engine off. Click the "Read" button and the codes will be displayed. Link any additional codes to the enclosed code table. Pay attention to these codes first.
• Instead of additional codes corresponding to code P2096 or P2098, test drive the vehicle and look for control symptoms. Fuel contamination will trigger this code. Add a higher class.
• If the car is showing very low power and difficulty accelerating, look under the car with the engine running. A clogged converter usually glows red.
• Check the engine for a vacuum leak between the MAF sensor and the intake manifold. Leaks often sound like a whistle. Eliminate any leaks and clean up the code.
• If the engine shows misfires and there was no code, determine which cylinder is misfiring. If the outlet manifold is visible, sprinkle or pour a small amount of water onto the outlet of each cylinder. The water will evaporate immediately on healthy cylinders and slowly on missing cylinders. If this is not possible, remove the plugs and check the condition.
• Look at the plug wires to make sure they are not burnt or lying on the exhaust.
• Inspect the exhaust system. Look for holes for rust, missing gaskets, cracks or looseness. Raise the vehicle and use a 7/8 ”wrench to make sure the oxygen sensor is tightened. Inspect the wire harness and connector.
• If an MAF sensor code is displayed, check its connector. If ok, replace the MAF sensor.
• Replace the oxygen sensor located downstream of the catalytic converter on the engine side without cylinder # 1. In addition, if the oxygen sensor code reports a "heater circuit malfunction", the sensor is most likely out of order.

Related DTC discussions

• BMW X2002 5 3.0 P2098 Fuel Trim System After Catalyst Bank 2 Too LeanHi. I came across some cucumber. I have a BMW X2002 5 3.0 year old and I am getting a “P2098 Post Catalyst Fuel Trim Bank 2 System Too Lean” with the check engine light on. I have already replaced the oxygen sensors before and after the catalytic converter (4 oxygen sensors have been replaced in total). Replaced mass air flow ... 
• Chrysler Crossfire P2007 2098 model year2007 Crossfire coupe convertible failed emissions. The dealer had a P2098 and a P0410 and said that a new oxygen sensor and main engine relay (5099007AA) must be replaced to start. I have replaced all oxygen sensors myself. It was cheaper than the dealer price for just one sensor (part). Still getting P2 ... 
• 2008L RAM 4.7 with codes P2096 and P2098I wonder if anyone has come across this before? I tried everything I could find and even got stumped at my local dealership ... .. 
• Ram p2098 and p1521 codes2006 ram 1500 5.7l floor. While driving on interstate codes p2098 and p1521, the light came on when the truck was moving and was idling. Standard truck, except for a new catalytic converter supplied to replace the missing truck…. 
• 07 dodge ram 1500 p2098 p2096 help codeOk guys, I need help here. I have a dodge ram 07 1500 hemi. From day one I had the code p2098 and p2096. All o2 sensors have been replaced with a new wiring harness, new spark plugs, new throttle body, vacuum leak fixed, it seems every time I put it back check engine li ... 
• Jeep wrangler 2005 p4.0 2098 model yeardoes anyone have a tip for 2098 ... 
• code P2098, low engine emissions bk 1 and 2code P2098, 06 jeep wrangler, v6, is there a simple solution for this, what to do first? ... 
• 2011 Grand Cherokee P0420, B1620, B1805, P2098Hi dear My 2011 Grand Cherokee, get this list of codes: P0420 B1620 B1805 C0a05 C0c96 P2098 Could you tell me what this means ?? Thank you very much… 
• 05 Jeep Liberty 3.7 code P2098Hello, I have a jeep liberty machine 05 3.7 with 123xxx. Before the p2098 code appeared last week, I had one cylinder misfire message. I had a compression test with a good spark from a coil with new spark plugs. I also tested the cats and they were good too. So my friend told me sea foam ... 
• P0430 & P2098 on 2008 chevrolet luminaThese two codes P0430 and P2098 are still present in my chevrolet lumina 2008. Please help ... 

Need more help with your p2098 code?

If you still need help with DTC P2098, post a question in the comments below this article.

NOTE. This information is provided for informational purposes only. It is not intended to be used as a repair recommendation and we are not responsible for any action you take on any vehicle. All information on this site is protected by copyright.