P0174: System Too Lean (Bank 2)
Severity: Moderate
What it means
Same as P0171 but on the other side of a V-type engine. Both together usually point to a shared cause.
Common symptoms
- Rough idle
- Hesitation
- Reduced power
Common causes
- Vacuum leak
- Dirty MAF sensor
- Low fuel pressure
What to check first
- If P0171 is also present, look for a cause that affects both sides (MAF, fuel pressure, big vacuum leak)
Causes vary by vehicle. Confirm with testing before replacing parts.
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