P2098

Post Catalyst Fuel Trim System Too Lean Bank 2

Q: Is it safe to drive with P2098?

Usually yes. It is often a small exhaust leak near the rear sensor rather than an engine problem, but repair it so the converter is properly monitored and you pass emissions.

Q: Can I just clear P2098?

It will return once the monitor runs again unless the leak, sensor, or lean condition is fixed.

Fuel & air metering (emissions) Generic OBD-II Low

What it means

P2098 means the fuel-trim correction based on the downstream (post-catalyst) oxygen sensor on bank 2 has hit its lean limit. In practice this is often a small exhaust leak near the rear sensor letting in extra air, an aging rear O2 sensor, or a genuine lean condition from a vacuum leak. The engine usually runs normally, but the fault should be fixed to keep the converter monitored and pass emissions.

Low

Can I keep driving? Usually driveable — the engine typically runs normally, but fix it to protect the catalytic converter and pass emissions; a genuine lean condition can cause mild rough running.

Real-world scan data

Seen in

108

scans in the past year

Found in

<0.1%

of scans

<0.1%

of scans that found faults

Figures reflect only diagnostic scans recorded through our own apps and tools. Cars are typically scanned because a symptom or warning light prompted it, so these counts describe our scan records — not the incidence of faults in any model, and not the quality, reliability, or safety of any vehicle. No comparison between manufacturers or models is implied. All trademarks belong to their respective owners; no affiliation or endorsement is implied.

Common symptoms

What you'll notice

Check-engine light on
Often no noticeable change in how the engine runs
Possible mild rough running or hesitation if the mixture is truly lean
May fail an emissions test

Common causes

Most likely first

Exhaust leak near the downstream (rear) oxygen sensor on bank 2 drawing in airLikely
Aged or faulty downstream oxygen sensor on bank 2Common
Vacuum or intake leak leaning out the mixtureCommon
Low fuel pressure or dirty injectors on bank 2Less often
Genuine lean running condition upstream (e.g. unmetered air)Less often

How to diagnose & fix

Work through it in order

Read freeze-frame data and review upstream fuel trims to see if the engine is actually lean.
Inspect the exhaust between the catalytic converter and the rear bank 2 oxygen sensor for leaks and repair any found.
Check for vacuum/intake leaks that could lean the mixture.
Verify fuel pressure and injector condition on bank 2 if trims are lean.
Test the downstream oxygen sensor and replace it if it is slow or biased with everything else in order.

FAQ

Quick answers

Is it safe to drive with P2098?+

Usually yes. It is often a small exhaust leak near the rear sensor rather than an engine problem, but repair it so the converter is properly monitored and you pass emissions.

Can I just clear P2098?+

It will return once the monitor runs again unless the leak, sensor, or lean condition is fixed.

Read & clear P2098 yourself

Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.

▶ Get it on Google Play

✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX