Acura bulletin B23-002
What it saysUnder certain circumstances, after coming to a stop and engaging idle stop the vehicle may not restart automatically due to excessive cylinder pressure and/or low cranking torque. NHTSA’s full summary ↓
Acura filed this with NHTSA as a service bulletin dated Jul 7, 2025, received Jan 11, 2023, about the electrical system — 3 documents under this number. It names 5 model years (2016–2020). 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 engaging idle stop the vehicle may not restart automatically due to excessive cylinder pressure and/or low cranking torque. Typically, the client can immediately restart the vehicle by selecting Park and pressing the ENGINE START/STOP button. NOTE: If 23-001 Product Update: PGM-FI Idle Stop Software Update is applicable to the VIN, the PGM-FI software must be updated first before the warranty extension applies. Acura is extending the warranty coverage for valve adjustment and starter replacement related to this condition to 10 years from the original date of purchase with no mileage limitation.
One of the 432 warranty extensions and special-coverage programs on file — every make, with the term each runs to.
Documents filed under this number
| Document | Kind | Dated | NHTSA id | At NHTSA |
|---|---|---|---|---|
| B23-002 | Service bulletin | Jul 7, 2025 | 11020584 | PDF, 2,327 KB |
| B23-002 | Service bulletin | Mar 20, 2023 | 10233292 | PDF, 976 KB |
| B23-002 | Service bulletin | Jan 6, 2023 | 10229688 | PDF, 975 KB |
What the document itself lists
The manufacturer titles it “Warranty Extension: Engine Does Not Auto Restart After Entering Auto”.
Parts the bulletin names
| Part number | Description | Qty | Find it |
|---|---|---|---|
| 17112-5G0-A01 | Intake Manifold Cover Gasket (Upper) | 1 | eBay Motors → |
| 17105-R9P-A01 | Intake Manifold Gasket | 1 | eBay Motors → |
| 16176-RYE-A10 | Throttle Body Gasket | 1 | eBay Motors → |
| 31200-5J2-A53 | Starter Motor Assy | 1 | eBay Motors → |
| 90051-5J4-000 | Flange Bolt (12X120) | 1 | eBay Motors → |
| 90165-SDA-A00 | Flange Bolt (12X45) | 2 | eBay Motors → |
| 39794-SDA-A03 | Power Relay Assy | 2 | eBay Motors → |
Labour operation and the time the manufacturer allows
| Operation | Description | Time |
|---|---|---|
| 1181FF | Replace the Starter, Starter Relays and Adjust Valves | 3 hrs |
Read by machine from the document NHTSA serves (14 pages), read Oct 4, 2026. A part number is shown only where it matches Acura’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.
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.
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.
Doing the repair yourself, or pricing it before the shop does? Search the part by fitment on eBay Motors — the listing and the price are the seller’s.
Find the software for the 2020 MDX →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.
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 5 model years this bulletin names have filed 1,247 complaints with NHTSA since 2015. 709 of them name Engine, Electrical System — 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 2016 Acura MDX, the 54 owners who gave an odometer reading for Engine reported it at a median of 66,701 miles. That figure is one model year’s, not the whole range this bulletin covers — medians from different model years are not averaged.
Our Acura MDX has continued to have Auto Idle Stop issues since we purchased the vehicle. Sometimes the vehicle would not restart after being stopped at a traffic light. Most recently, an accident almost occurred when the vehicle stuck behind us at the traffic light tried to go around us while we were trying to get the engine started and…
2020 Acura MDX · Engine · filed with NHTSA May 23, 2023 · ODI 11523509
Yesterday while stopped a light, the Mdx refused to move once I took my foot off the break. The engine became very loud and 'emissions system problem' and 'brake parking problem' appeared on the dashboard. The trunk opened but wdnt close automatically. I had to have the vehicle towed to the dealer.
2017 Acura MDX · Engine · filed with NHTSA Sep 9, 2018 · ODI 11128347
In San Diego on 11/15/2021, my daughter side swiped a parked vehicle in residential area driving about 30 miles. No airbags deployed. A minute later the car stopped and would not start and started to have smoke and flames come from under hood and through inside windshield and dash.
2018 Acura MDX · Electrical System · filed with NHTSA Dec 6, 2021 · ODI 11442765
In depth: 2020 Acura MDX engine problems → · 2019 Acura MDX engine problems → · 2018 Acura MDX engine problems → · 2017 Acura MDX 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 electrical system
Source: same model, same component group21 other manufacturer communications filed against the Acura MDX under the same component group (electrical system), newest first. The eight newest are listed; the rest are on the Acura list.
| Number | Kind | Dated | NHTSA’s summary |
|---|---|---|---|
| BBTS30565 | Other | Apr 7, 2026 | Tech Line Summary - The vehicle's infotainment system displays previously viewed SMS messages upon each ignition cycle, when the customer's… |
| 8A050-TYA-A017 | Over-the-air update | Mar 10, 2026 | Over The Air System Updates - Vehicles equipped with the System Updates application are capable of downloading and installing Over the Air S… |
| 8A050-TYA-A016 | Over-the-air update | Jan 17, 2026 | Over the Air System Update - System updates contain upgrades that fix operational errors and/or provide a variety of enhancements, which add… |
| BB29050 | Other | Aug 4, 2025 | Tech Line - Customers may experience error code S001 with their audio unit. The vehicle may also have DTC B2B05-92 CAN Gateway error stored… |
| BTI&05162025901 | Other | May 16, 2025 | Dealer Message - American Honda Motor Co., Inc. (AHM) is searching for certain 2025 MDX’s with a client complaint of no sound while making A… |
| B24-047 | Service bulletin | Dec 18, 2024 | Service Bulletin - A coaxial cable terminal was not manufactured to proper specifications. An improperly manufactured terminal may lead to p… |
| B24-058 | Service bulletin | Dec 17, 2024 | Service Bulletin - Under certain circumstances when reversing near a chain-link fence or highly reflective surfaces, a parking and back-up s… |
| ONL6M309172024 | Other | Sep 18, 2024 | Owner Notification Letter - A coaxial cable terminal was not manufactured to proper specifications. An improperly manufactured terminal may… |
Quote the number at the service desk. It is what the dealer’s system is keyed on.
Every manufacturer communication NHTSA holds for Acura, by the number printed on the letter.
Common questions
Source: NHTSA, 49 CFR 579.5Is Acura B23-002 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 B23-002 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 B23-002 cover?
The manufacturer filed it against 5 model years: 2020 Acura MDX, 2019 Acura MDX, 2018 Acura MDX, 2017 Acura MDX, 2016 Acura MDX. Whether one particular vehicle is affected is a matter of its VIN and its build, not its model year alone.