P0172 on Honda vehicles The engine is running rich on bank 1: too much fuel for the air going in

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.

Owners’ own words, scrubbed of anything identifying. Unverified reports filed with NHTSA — what was said, not a finding that it was true.

Bulletins and campaigns Honda filed with NHTSA whose summary names P0172. Quote the document number at the service desk — it is a diagnosis the maker has already written down.

• A18-114 Service bulletin
  2018-10-22 · Engine And Engine Cooling
• Service bulletin - Under certain circumstances, the vehicle may experience driveability concerns, which may result in DTC's P0300 (Random Misfire Detected), P0301 (No. 1 Cylinder Misfire Detected), P0302 (No. 2 Cylinder Misfire Detected), P0303 (No. 3 Cylinder Misfire Detected), P0304 (No. 4 Cylinder Misfire Detected), or P0172 (Fuel System Too Rich) to set.
• A18-124 Service bulletin
  2018-10-22 · Engine And Engine Cooling
• Service bulletin - Under certain circumstances, the vehicle may experience driveability concerns, which may result in DTC's P0300 (Random Misfire Detected), P0301 (No. 1 Cylinder Misfire Detected), P0302 (No. 2 Cylinder Misfire Detected), P0303 (No. 3 Cylinder Misfire Detected), P0304 (No. 4 Cylinder Misfire Detected), or P0172 (Fuel System Too Rich) to set.
• A18-114 Service bulletin
  2018-12-07 · Equipment — Appliance — Air Conditioner
• "Service bulletin - Under certain circumstances, the vehicle may experience driveability concerns, which may result in DTC's P0300 (Random Misfire Detected), P0301 (No. 1 Cylinder Misfire Detected), P0302 (No. 2 Cylinder Misfire Detected), P0303 (No. 3 Cylinder Misfire Detected), P0304 (No. 4 Cylinder Misfire Detected), or P0172 (Fuel System Too Rich) to set."
• ATI&06152021904 Service bulletin
  2021-06-15 · Fuel System, Gasoline
• Dealer Message - American Honda Motor Co., Inc. (AHM) is searching for certain 2018-2021 Accord 1.5Ts, Civic Sis & CR-Vs with a customer complaint of the Malfunction Indicator Light (MIL) on with the DTC P030X (Cylinder Misfire Detected) or P0172 (Fuel System Too Rich) stored. To better understand the cause of this condition, AHM would like to collect specific parts from the vehicle prior to you a
• ATI&07012021 Service bulletin
  2021-07-01 · Fuel System, Gasoline
• Dealer Message - American Honda Motor Co., Inc. (AHM) is searching for certain 2018-2021 Accord 1.5Ts, Civic Sis & CR-Vs with a customer complaint of the Malfunction Indicator Light (MIL) on with the DTC P030X (Cylinder Misfire Detected) or P0172 (Fuel System Too Rich) stored. To better understand the cause of this condition, AHM would like to collect specific parts from the vehicle prior to you a
• ATI&07202021901 Service bulletin
  2021-07-20 · Fuel System, Gasoline
• Dealer Message - American Honda Motor Co., Inc. (AHM) is searching for certain 2018-2021 Accord 1.5Ts, Civic Sis & CR-Vs with a customer complaint of the Malfunction Indicator Light (MIL) on with the DTC P030X (Cylinder Misfire Detected) or P0172 (Fuel System Too Rich) stored. To better understand the cause of this condition, AHM would like to collect specific parts from the vehicle prior to you a
• A19-027 Service bulletin
  2019-03-05 · Equipment — Appliance — Air Conditioner
• Service Bulletin - Under certain circumstances, the vehicle may experience driveability issues, which may result in DTCs P0300 (random misfire detected), P0301 (No. 1 cylinder misfire detected), P0302 (No. 2 cylinder misfire detected), P0303 (No. 3 cylinder misfire detected), P0304 (No. 4 cylinder misfire detected), or P0172 (fuel system too rich) to set.
• A19-012 Service bulletin
  2019-04-05 · Equipment
• 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. If you did Service Bulletin 19-012 on or before April 5th, 2019, use the Warranty Claim Information provided below.
• APaS06072022901 Service bulletin
  2022-06-07 · Engine And Engine Cooling
• Dealer message - American Honda Motor Co., Inc. (AHM) is searching for certain 2019-2022 Accord 1.5T & 2020-2022 1.5T CR-Vs with a customer complaint of the Malfunction Indicator Light (MIL) on with the DTC P030X (Cylinder Misfire Detected) or P0172 (Fuel System Too Rich) stored. To better understand the cause of this condition, AHM would like to collect specific parts from the vehicle prior to yo
• APaS07052022901 Service bulletin
  2022-07-05 · Fuel System, Gasoline
• Dealer message - American Honda Motor Co., Inc. (AHM) is searching for certain 2019-2022 Accord 1.5T & 2020-2022 1.5T CR-Vs with a customer complaint of the Malfunction Indicator Light (MIL) on with the DTC P030X (Cylinder Misfire Detected) or P0172 (Fuel System Too Rich) stored. To better understand the cause of this condition, AHM would like to collect specific parts from the vehicle prior to yo
• ATI&07212022901 Service bulletin
  2022-07-21 · Fuel System, Gasoline
• Dealer message - American Honda Motor Co., Inc. (AHM) is searching for certain 2019-2022 Accord 1.5Ts & 2020-2022 CR-V 1.5Ts with a customer complaint of the Malfunction Indicator Light (MIL) on with the DTC P030X (Cylinder Misfire Detected) or P0172 (Fuel System Too Rich) stored. To better understand the cause of this condition, AHM would like to collect specific parts from the vehicle prior to y
• A19-012 Service bulletin
  2023-01-11 · 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.

A stored code names the test that failed, never the part that caused it. The record above is what Honda and its owners have filed about it; the code’s page across every make has the whole file.