Back to 2011 Audi A4

2011 AUDI A4

2.0L Turbo I4AWDAUTOMATICgasturbo
Repairs0Labor501Torque3710Fluid9DTC894Battery0Maintenance0Recalls0
P0139low severityPowertrain

O2 Sensor Circuit Slow Response Bank 1 Sensor 2

on 2011 Audi A4 2.0L Turbo I4 · AWD

What this code means

The downstream O2 sensor on Bank 1 is responding too slowly.

Symptoms

  • Check Engine Light
  • Failed emissions

Common causes

  • Aging sensor
  • Contaminated sensor
  • Catalyst issue

Diagnostic steps

  1. Monitor sensor response
  2. Check catalyst efficiency

Repair notes

Replace downstream O2 sensor.

Other Powertrain codes on this vehicle

Building an app?
Free API access to all this data — 50 requests/day, no card required.
Get an API key →
Run a shop?
Manage repairs, estimates, and customers with ShopBase — $249/mo, all features included.
Try ShopBase →