P0171 on Buick vehicles The engine is running lean on bank 1: too much air, or not enough fuel, for the mixture the computer wants
P0171 is named on 14 Buick model years (2016–2019): 50 manufacturer filings and 2 owner reports in NHTSA’s files, across Encore, Enclave, Envision, Regal, LaCrosse and 1 more.
Which Buick model years name P0171
Source: NHTSA manufacturer communications and complaints| Model year | Filed under | Bulletins | Owner reports |
|---|---|---|---|
| 2018 Buick Encore | Engine | 5 | 2 |
| 2016 Buick Encore | Engine | 6 | — |
| 2018 Buick Enclave | Fuel/Propulsion System | 5 | — |
| 2017 Buick Enclave | Fuel/Propulsion System | 5 | — |
| 2017 Buick Encore | Engine | 5 | — |
| 2016 Buick Enclave | Fuel/Propulsion System | 5 | — |
| 2019 Buick Encore | Electrical System | 3 | — |
| 2017 Buick Envision | Electrical System | 3 | — |
| 2017 Buick Regal | Electrical System | 3 | — |
| 2016 Buick Envision | Electrical System | 3 | — |
| 2016 Buick Regal | Electrical System | 3 | — |
| 2017 Buick LaCrosse | Engine | 2 | — |
| 2019 Buick Cascada | Engine | 1 | — |
| 2016 Buick Cascada | Engine | 1 | — |
A model year is listed because the code is named in its own record — a bulletin filed against it, or an owner’s complaint about it — not because every one of these vehicles sets it. Counts are documents in NHTSA’s files, not failure rates.
What Buick owners said
Source: NHTSA complaint databaseOwners’ own words, scrubbed of anything identifying. Unverified reports filed with NHTSA — what was said, not a finding that it was true.
My vehicle had a check engine light code of P0171 and the odor of burning oil
Buick filings that name P0171
Source: NHTSA manufacturer communicationsBulletins and campaigns Buick filed with NHTSA whose summary names P0171. Quote the document number at the service desk — it is a diagnosis the maker has already written down.
- PIP5240D Service bulletin2018-04-27 · Engine And Engine Cooling
- This Preliminary Information communication provides information to the technician about vehicles that may have a Malfunction Indicator Lamp on. Technician may find Diagnostic Trouble Codes P0171 and or P1101 set. Technician will need to inspect the Air Cleaner Housing. If the air cleaner housing does not have the correct content for the engine application as shown, dealer is instructed to replace
- PIP5240E Service bulletin2018-05-15 · Engine
- This Preliminary Information communication provides information to the technician about vehicles that may have a Malfunction Indicator Lamp on. Technician may find Diagnostic Trouble Codes P0171 and or P1101 set. Technician will need to inspect the Air Cleaner Housing. If the air cleaner housing does not have the correct content for the engine application as shown, dealer is instructed to replace
- 19NA114 Service bulletin2019-05-15 · Electrical System
- This informational bulletin provides information to the tech to test the PCV for proper performance before replacing the camshaft cover to correct a MIL On w/DTC P0171.
- PIP5240A Service bulletin2017-01-25 · Engine And Engine Cooling — Cooling System
- This Preliminary Information communication provides information to the technician about vehicles that may have a Malfunction Indicator Lamp on. Technician may find Diagnostic Trouble Codes P0171 and or P1101 set. Technician will need to inspect the Air Cleaner Housing Identification Code. If the Hydro Carbon Absorber is missing, or the Identification code is other than ACD, replace the Air Cleaner
- PIE0433A Service bulletin2017-10-31 · Fuel System, Gasoline
- This engineering informational bulletin is requesting information from the field on vehicles that have the condition of Engineering Information ? Malfunction Indicator Lamp (MIL) On DTCs P0171 Fuel Trim System Lean Bank 1 and/or P0174 Fuel Trim System Lean Bank 2.
- PIE0433A Service bulletin2017-12-21 · Electrical System — Software
- This engineering informational bulletin is requesting information from the field on vehicles that have the condition of Engineering Information ? Malfunction Indicator Lamp (MIL) On DTCs P0171 Fuel Trim System Lean Bank 1 and/or P0174 Fuel Trim System Lean Bank 2.
- PIE0433A Service bulletin2017-11-28 · Fuel System, Gasoline
- This engineering informational bulletin is requesting information from the field on vehicles that have the condition of Engineering Information ? Malfunction Indicator Lamp (MIL) On DTCs P0171 Fuel Trim System Lean Bank 1 and/or P0174 Fuel Trim System Lean Bank 2.
- 19NA114 Service bulletin2019-05-15 · Electrical System
- This informational bulletin provides information to the tech to test the PCV for proper performance before replacing the camshaft cover to correct a MIL On w/DTC P0171.
- PIP5240F Service bulletin2019-07-25 · Equipment — Appliance — Air Conditioner
- This Preliminary Information communication provides information to the technician about vehicles that may have a Malfunction Indicator Lamp on. Technician may find Diagnostic Trouble Codes P0171 and or P1101 set. Technician will need to inspect the Air Cleaner Housing. If the air cleaner housing does not have the correct content for the engine application as shown, dealer is instructed to replace
- PIP5529 Service bulletin2017-10-20 · Equipment — Other — Owners/Service/Other Manual
- This Preliminary information communicates additional diagnosticsand repairto assist in resolving a malfunction indicator lampillumination due to any combination of diagnostic trouble codes P0068 P0101 P0106 P0171 P0131 P0137 P0324 P0326 P0331 P0506.
- PIP5529A Service bulletin2018-02-28 · Electrical System — Instrument Cluster/Panel
- This Preliminary information communicates additional diagnosticsand repairto assist in resolving a malfunction indicator lampillumination due to any combination of diagnostic trouble codes P0068 P0101 P0106 P0171 P0131 P0137 P0324 P0326 P0331 P0506.
- PIP5529B Service bulletin2019-09-06 · Electrical System
- This Preliminary information communicates additional diagnostics and repair to assist in resolving a malfunction indicator lamp illumination due to any combination of diagnostic trouble codes P0068 P0101 P0106 P0171 P0131 P0137 P0324 P0326 P0331 P0506.
What P0171 means
Source: SAE J2012 / OBD-IIThe engine is running lean on bank 1: too much air, or not enough fuel, for the mixture the computer wants.
A stored code names the test that failed, never the part that caused it. The record above is what Buick and its owners have filed about it; the code’s page across every make has the whole file.
Common questions
Source: NHTSA files and the OBD-II standardIs P0171 a known problem on Buick vehicles?
It is a documented one: NHTSA's files hold 50 manufacturer filings and 2 owner reports naming P0171 on 14 Buick model years (2016–2019). Whether it is a problem on one particular car is a diagnosis, not a count — but a bulletin that names the code on your model year is the place to start.
Which Buick models does P0171 appear on most?
2018 Encore (7 documents), 2016 Encore (6 documents), 2018 Enclave (5 documents).
Does P0171 on a Buick mean it is recalled?
No. Recalls are filed by campaign and matched by VIN; no recall is triggered by a scan tool. Check the VIN at nhtsa.gov/recalls, or open the model year's page here for the campaigns filed against it.