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1998 AUDI A3

1.6L I4FWDAUTOMATICgas
Repairs0Labor472Torque2472Fluid6DTC645Battery0Maintenance0Recalls0
P2204moderate severityPowertrain

NOx Sensor Circuit Intermittent Bank 1

on 1998 Audi A3 1.6L I4 · FWD

What this code means

Intermittent signal from the NOx sensor on bank 1.

Symptoms

  • Intermittent check engine light
  • Erratic SCR operation

Common causes

  • Loose connection
  • Damaged wiring
  • Sensor connector moisture ingress

Diagnostic steps

  1. Wiggle test wiring and connector
  2. Check for water intrusion
  3. Monitor signal stability

Repair notes

Clean and secure connector. Replace sensor or repair wiring if intermittent.

Other Powertrain codes on this vehicle

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