P2098Post Catalyst Fuel Trim System Too Lean (Bank 2)
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Needs a drive cycle to confirm a fix
- How the car detects it
- P2098 is the bank 2 version of P2096 on V and flat engines with a catalyst and rear oxygen sensor per bank. The post-catalyst trim of bank 2 has reached its lean-side limit because the rear sensor of that bank keeps reporting rich exhaust. Ford monitors both banks the same way and sets the code 5 s after the bank 2 rear bias trim reaches -0.083; GM's Bosch-based 2005 2.8 and 3.6 V6 and the 2008 3.6 LLT list it as a rich shift of the secondary trim beyond its calibrated limit. If only one bank reports it, compare the two banks' rear sensor signals and the front sensor readings: a fault on one side points to that bank's sensors or its exhaust, whereas both banks together hint at a common cause such as fuel or calibration. Audi saw P2098 with P2096 on 2013 to 2016 A8, S6, S7, S8, RS 6 and RS 7 4.0 TFSI, caused by contaminated reference air ducts in the rear sensors, not by the front sensors the guided test suggests.
- What you may notice
- Malfunction indicator lamp on
- Usually no noticeable change in driveability
- Likely causes
- LikelyBank 2 rear oxygen sensor skewed rich
- PossibleBank 2 front sensor reading lean
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Often possible to do yourself.Typical cost: €0 – €300
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.