P0172 The engine is running rich on bank 1: too much fuel for the air going in
73 owner reports and 509 manufacturer filings across 137 model years from Audi, BMW, Buick, Cadillac and others.
Where P0172 shows up
Source: NHTSA manufacturer communications and complaintsShowing the 25 model years where P0172 appears most; it is on file for 137 in total.
A model year appears here because the code is named in its record, not because every one of these vehicles sets it. Counts are mentions in the federal files, not failure rates — nobody publishes the denominator.
Affiliate disclosure: some links on this page are affiliate links. If you request a quote or buy through them we may earn a commission at no extra cost to you. Nothing on this page changes because of it.
P0172 by make
The same record, one make at a time: the model years, bulletins and owner reports that name P0172 on that maker’s vehicles.
What it gets filed under
What owners said
Source: NHTSA complaint databaseOwners’ own words, one per nameplate, scrubbed of anything identifying. These are unverified reports filed with NHTSA — they are what was said, not a finding that it was true.
I took the vehicle to a certified Honda dealership, where technicians officially diagnosed the issue as a "Fuel System Too Rich" condition (Diagnostic Trouble Code P0172)
Furthermore, there is a data discrepancy: the dealership pulled diagnostic trouble code P0172, but corporate claims the vehicle threw code P0173 and is withholding the physical diagnostic printout behind a fee paywall
My engine light came on, and the codes reported were P0441 P04F1 U0401 and P0172
On July 25, another diagnostic showed Check Engine FAIL with codes P0172, P0455 and P0456
· Active Diagnostic Trouble Codes (DTCs) stored: P0017, P0014, P000B, P0172, P0300, P0301, P0302, P0303, P0304
509 manufacturer filings name P0172. Start with what the maker wrote down.
A code names the test that failed, not the part. A bulletin that names it is often a diagnosis someone has already written down — quote its number at the service desk.
Manufacturer filings that name it
Source: NHTSA manufacturer communicationsService bulletins and campaigns whose filed summary names P0172.
- PIP6115 Service bulletin2026-05-21 · Unknown Or Other
- The document advise technicians after an engine repair involving removal of the camshaft actuators, the vehicle may set p1101 P0172 and or stalls when taken off idle. The technician is instructed to verify the intake and exhaust camshaft actuators are installed onto the correct camshafts.
- PIP6113 Service bulletin2026-05-19 · Unknown Or Other
- This document provides the technician with a diagnostic tip if the vehicle stalls and set diagnostic trouble code P0191 and may also set P0172. The diagnostic tip has the technician inspect the high pressure fuel pump body markings to confirm it is an original manufacture part. If it is not an original manufacture part, they should install one and evaluate the vehicle.
- A25-044 Service bulletin2025-07-08 · Engine
- Service Bulletin - The engine runs rough and makes a rattling noise, accompanied by DTC P0134 or P0135 due to a possible fuel injector leak causing a rich air/fuel (A/F) mixture that fouls the spark plug(s) and causing the PCM to misread the A/F sensor heater resistance. Other DTCs may also include: P0700, P0300, P219C, P219D, P219E, P219F, P0172.
- 22-NA-128 Service bulletin2024-08-09 · Fuel/Propulsion System
- This technical bulletin provides a procedure to test the intake manifold for any possible leaks that may cause the customers concern of a Malfunction Indicator Lamp (MIL) Illuminated - DTC P0172, P026D, P2459, and/or P2A00 Set.
- 22-NA-128 Service bulletin2024-05-30 · Engine
- This technical bulletin provides a procedure to test the intake manifold for any possible leaks that may cause the customers concern of a Malfunction Indicator Lamp (MIL) Illuminated - DTC P0172, P026D, P2459, and/or P2A00 Set.
- A19-012 Service bulletin2023-01-11 · Visibility
- Service Bulletin - This bulletin is replaced by S/B 19-033, Warranty Extension: 2016-18 Civic 1.5L: Software Update with A/C Control Unit Replacement; DTC P0300, P0301, P0302, P0303, P0304, or P0172; Whirling Noise from Engine.
What P0172 means
Source: SAE J2012 / OBD-IIThe engine is running rich on bank 1: too much fuel for the air going in.
A stored code names the test that failed, never the part that caused it. It is the starting point of a diagnosis, not its conclusion — the same code has several possible causes and the cheap one is not always right.
Common questions about P0172
Source: NHTSA files and the OBD-II standardCan I keep driving with P0172 stored?
Nobody can answer that from the code alone, and a site that does is guessing. A steady light means a fault was logged and the car should be checked soon; a flashing light means a severe misfire — slow down and get it seen as soon as possible, because severe misfire can quickly damage the catalytic converter. The safe read of this page is the mileage and the components, not permission.
Does a code mean the car is recalled?
No. Recalls are filed by campaign and matched by VIN, and none of them are triggered by a scan tool. If you want to know whether an open recall applies to one specific vehicle, check the VIN at nhtsa.gov/recalls — that is the only source that settles it.
Why do the counts here differ from other sites?
Because these are not estimates. Every number on this page is a count of documents in NHTSA's own files: manufacturer communications that name the code in their filed summary, and owner complaints that name it in the narrative. We do not model, weight or extrapolate them.
Will clearing the code fix it?
Clearing turns the light off and erases the freeze-frame data a technician would have used to work out what happened. If the condition is still there the code returns, usually within a few drive cycles, and the diagnosis now starts from less information than before.