P0174high severityPowertrain
System Too Lean Bank 2
on 2007 Audi Q7 4.2L V8 · AWD
What this code means
The long-term fuel trim for Bank 2 has exceeded the positive limit, indicating lean running on Bank 2.
Symptoms
- Check Engine Light
- Rough idle
- Hesitation
- Possible misfires
Common causes
- Vacuum leak Bank 2 side
- Low fuel pressure
- Faulty MAF sensor
- Exhaust leak Bank 2
- Clogged injector Bank 2
Diagnostic steps
- Check fuel trim Bank 2
- Smoke test Bank 2 intake
- Test fuel pressure
- Test MAF sensor
- Check for exhaust leaks Bank 2
Repair notes
Same diagnostic approach as P0171 but focused on Bank 2.
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