p0174
Moderate
Audi · SUVs
System Too Lean Bank 2
Quick Answer
Error code P0174 on your Audi SUVs means: System Too Lean Bank 2. This is usually fixable — see the step-by-step guide below.
Affected Models
Applies to all models
F3FY4M4MNGENGE
Likely Causes
  1. Vacuum leak affecting bank 2 cylinders
  2. MAF sensor underreporting airflow
  3. Low fuel pressure or restricted fuel supply
  4. Cracked intake boot allowing unmetered air
  5. Bank 2 oxygen sensor sending inaccurate feedback
How to Fix It
1
Check for related codes on both banks to determine scope of the issue
2
Smoke test the intake system with focus on bank 2 connections
3
Inspect the intake boot between the MAF sensor and throttle body
4
Test fuel pump pressure and volume delivery
5
Monitor bank 2 oxygen sensor data for abnormal readings
Pro Tip
This fix requires some technical knowledge. If you're unsure about any step, consider contacting support or a qualified technician.
Parts You May Need
MAF sensor
Intake boot
Vacuum lines
O2 sensor (bank 2)
Related Error Codes
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