P0171 on Chevrolet Vehicles: System Too Lean (Bank 1)
The engine computer is adding the maximum extra fuel it's allowed on bank 1 and still sees a lean mixture. P0171 →
30Complaints mentioning the code
#1Rank among 18 brands
2.4%Share of Chevrolet DTC complaints
In NHTSA owner complaints we analyzed for Chevrolet, P0171 was mentioned 30 times.
Most mentioned models
| Chevrolet Cruze | 10 | |
|---|---|---|
| Chevrolet Sonic | 6 | |
| Chevrolet Malibu Eco Eassist | 3 | |
| Chevrolet Traverse | 3 | |
| Chevrolet Equinox | 2 | |
| Chevrolet Trax | 2 |
Model years mentioned
Components named in these complaints
- Engine (19)
- Electrical System (8)
- Fuel/propulsion System (8)
- Power Train (5)
- Unknown Or Other (4)
Reports with a crash: 1 · fire: 0 · injuries: 5
Often appears together with
P0106
Powertrain
The MAP sensor works electrically, but its pressure reading doesn't fit what the engine…
Low
P0131
Powertrain
The upstream oxygen sensor on bank 1 keeps reporting a voltage so low that it reads as a lean…
Low
P0300
Powertrain
The engine computer sees misfires that jump between cylinders or hit several cylinders at once.
High
P0121
Powertrain
The throttle position reading is electrically valid but doesn't agree with engine load, airflow…
Moderate
P0174
Powertrain
The cylinder bank without cylinder 1 is running lean even with the maximum fuel correction…
Moderate
Possible causes
- Vacuum leak: cracked PCV hose or failed PCV valve, intake manifold gasket, brake booster hose
- Dirty or failing MAF sensor reading less air than is actually entering
- Low fuel pressure or volume (weak fuel pump, clogged filter or strainer, faulty regulator)
- Exhaust leak ahead of the upstream O2 sensor drawing in outside air
Related codes
Source: NHTSA Complaints API (US government open data), analyzed by DTC mention.