Honda bulletin A23-027
What it saysUnder certain circumstances, after coming to a stop and the idle stop feature engages, the vehicle may not automatically restart. NHTSA’s full summary ↓
Honda filed this with NHTSA as a service bulletin dated Jul 26, 2023, received Aug 3, 2023, about the engine. It names 6 model years (2018–2023). A service bulletin is not a safety recall: it is the manufacturer telling its dealers how to diagnose or repair a condition, and whether the work is paid for depends on the warranty in force. Quoting the number at a service desk can save a diagnosis.
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What the bulletin says
Source: NHTSA's summary of the manufacturer's communicationService Bulletin - Under certain circumstances, after coming to a stop and the idle stop feature engages, the vehicle may not automatically restart. Typically, the customer can immediately restart the vehicle by selecting Park and pushing the ENGINE START/STOP button.
Document filed under this number
| Document | Kind | Dated | NHTSA id | At NHTSA |
|---|---|---|---|---|
| A23-027 | Service bulletin | Jul 26, 2023 | 10240336 | PDF, 201 KB |
What the document itself lists
Part the bulletin names
| Part number | Description | Qty | Find it |
|---|---|---|---|
| 37805-5MR-C12 | — | — |
Labour operation and the time the manufacturer allows
| Operation | Description | Time |
|---|---|---|
| 1255D8 | Update the PGM-FI software | 0.2 hrs |
Read by machine from the document NHTSA serves (3 pages), read Oct 4, 2026. A part number is shown only where it matches Honda’s own catalogue shape, an operation only with its code and time, and a description only where the reader got it whole; anything it could not settle is left out, and the PDF is the record. Times are the manufacturer’s warranty allowances, not a quote. Listings and prices on eBay Motors are the seller’s.
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The summary is NHTSA’s abstract of the document, as filed under 49 CFR 579.5. One communication is usually filed as several documents — the bulletin, a dealer notice, an owner letter — and the number on any of them finds this page. A PDF link is shown only once NHTSA’s own server has been seen to serve that document; the rest are checked over the following nights. Quote the number at a service desk; it is what the dealer’s system is keyed on.
Model years it names
Source: as the manufacturer filed themA vehicle page’s bulletin list shows the newest few communications filed against that model year; the count there is every one.
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What owners reported
Source: NHTSA complaint databaseOwners of the 6 model years this bulletin names have filed 2,897 complaints with NHTSA since 2015. 479 of them name Engine — the same broad component group this bulletin is filed under. NHTSA groups complaints coarsely, so that means the same area of the vehicle, not necessarily the same fault.
On the 2018 Honda Odyssey, the 41 owners who gave an odometer reading for Engine reported it at a median of 93,533 miles. That figure is one model year’s, not the whole range this bulletin covers — medians from different model years are not averaged.
Car has under 7000 miles. Engine struggles with power in lower gears. There is also a jump when shifting from reverse to forward. The jump feel like a transmission gear transfer issue. Today as an example, when departing from a traffic light, I had to fully compress the gas pedal to get the engine to respond.
2019 Honda Odyssey · Engine · filed with NHTSA Jun 19, 2019 · ODI 11221239
In depth: 2020 Honda Odyssey engine problems → · 2019 Honda Odyssey engine problems → · 2018 Honda Odyssey engine problems →
A complaint is one owner’s account, not a defect finding, and a bulletin is not a recall. Nothing here says this bulletin was issued because of these complaints, or that the repair it describes fixed them. Complaint files on this site begin in 2015.
More bulletins about the engine
Source: same model, same component group21 other manufacturer communications filed against the Honda Odyssey under the same component group (engine), newest first. The eight newest are listed; the rest are on the Honda list.
| Number | Kind | Dated | NHTSA’s summary |
|---|---|---|---|
| ATI&05122026902 | Other | May 13, 2026 | Dealer Message - American Honda Motor Co., Inc. (AHM) is searching for certain 2024-2026 Odysseys & Ridgelines and 2024-2025 Passports with… |
| ATI&04292026901 | Other | Apr 29, 2026 | Dealer Message - American Honda Motor Co., Inc. (AHM) is searching for certain 2024-2026 Odysseys & Ridgelines and 2024-2025 Passports with… |
| A26-001 | Service bulletin | Feb 1, 2026 | Service Bulletin - The piston ring function deteriorates due to ring low wear toughness and sticking from sludge. Oil adheres to the spark p… |
| A25-061 | Service bulletin | Aug 29, 2025 | Service Bulletin - The piston ring function deteriorates due to ring wear and sticking from sludge. Oil from the crankcase adheres to the sp… |
| ATI&07312025905 | Other | Aug 1, 2025 | Dealer Message - American Honda Motor Co., Inc. (AHM) is searching for certain 2023-2025 Odysseys, Passports, and Ridgelines with a customer… |
| ONL6Z6072025 | Other | Jul 29, 2025 | Owner Notification Letter - the piston ring function can deteriorate due to ring low wear toughness and sticking from sludge. Oil adheres to… |
| ATI&07152025901 | Other | Jul 15, 2025 | Dealer Message - American Honda Motor Co., Inc. (AHM) is searching for certain 2023-2025 Odysseys, Passports, and Ridgelines with a customer… |
| AEBM06172025901 | Other | Jun 17, 2025 | Dealer Message - Piston ring effectiveness may be reduced due to excessive wear and oil sludge build-up, which can cause oil to adhere to th… |
Quote the number at the service desk. It is what the dealer’s system is keyed on.
Every manufacturer communication NHTSA holds for Honda, by the number printed on the letter.
Common questions
Source: NHTSA, 49 CFR 579.5Is Honda A23-027 a recall?
No. A service bulletin is a manufacturer communication filed with NHTSA under 49 CFR 579.5; a safety recall carries an NHTSA campaign number (two digits, a letter, six digits) and a federal duty to repair for free. Check the vehicle’s recalls by VIN at nhtsa.gov/recalls, or on its page here.
Is the A23-027 repair free?
Not automatically. A service bulletin describes how to diagnose or repair a condition; who pays depends on the warranty in force, any extension, and the dealer. Quoting the number can save a diagnosis either way. Every Honda warranty extension on file lists the ones Honda has filed.
Which vehicles does A23-027 cover?
The manufacturer filed it against 6 model years: 2023 Honda Odyssey, 2022 Honda Odyssey, 2021 Honda Odyssey, 2020 Honda Odyssey, 2019 Honda Odyssey, 2018 Honda Odyssey. Whether one particular vehicle is affected is a matter of its VIN and its build, not its model year alone.