OBD-II code · Powertrain (generic, extended)

P2BA4 Catalyst Feedgas Performance

The ECM detects that the exhaust gas composition reaching the catalyst (feedgas) deviates from the calibrated profile. Pre-cat O2 measurement and air-fuel control are inconsistent with engine operation.

Is it safe to drive with P2BA4?

Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.

Common causes

  • Most likelyLong-term fuel trim drifted out of nominal range
  • PossibleExhaust leak upstream of catalyst

Symptoms

  • Check engine light on
  • Failed emissions inspection
  • Possibly slightly increased fuel consumption
  • Sulfur (rotten egg) smell from exhaust under load

Repair at a glance

Difficulty
Medium
DIY friendly
Best left to a mechanic
Typical labour
1–6 h
Emissions test
Likely to fail
After the fix
A drive cycle is needed before the light stays off
Parts involved
Catalytic Converter, O2 Sensor Pre Cat, Ecm

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.