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TSB 23-008 PGM-FI Idle Stop Software Update (2016-2022) and TSB 23-010 Warranty Extension (2021-2022)

13110 Views 76 Replies 35 Participants Last post by  osimj
TSB 23-008 Product Update: PGM-FI Idle Stop Software Update (2016-2022)


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.

Owners of affected vehicles will be sent a notification of this product update. Do an iN VIN status inquiry to verify eligibility. Some vehicles affected by this campaign may be in your new or used vehicle inventory. Repair these vehicles before they are sold.

Update the PGM-FI Software. NOTE: The software update will decrease the Idle Stop operating range. As a result, the customer may notice reduced idle stop engagement when their vehicle’s battery is approaching the end of its useful life.

TSB 23-010 Warranty Extension: Engine Does Not Auto Restart After Entering Auto Idle Stop (2021-2022)


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 customer can immediately restart the vehicle by selecting Park and pressing the ENGINE START/STOP button. NOTE: If 23-008 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. Honda is extending the warranty coverage for valve adjustment to 10 years from the original date of purchase with no mileage limitation.

Owners of affected vehicles will be sent a notification of this campaign. Do an iN VIN status inquiry to verify eligibility.

Adjust the valves.


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Thank you for that! It appears to be a product update and warranty extension, which probably explains why it doesn't appear on NHTSA's website or Honda's website as a safety recall.
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The 2023 RL is included in the valve adjustment warranty extension but the 2023 PP is not included. I don’t understand why the 2023 PP would not be included.
I don't know how this works, so this is pure speculation. It's possible that the updated software was included in the 2023 Passport's design package, so it's got the updated calibrations from the factory. Perhaps the 2023 Ridgeline's final design package was already set prior to this new software having been developed. Maybe they start including it on 2023 Ridgelines as a rolling change...which is where the VIN would come into play -- Honda would know which 2023 Ridgelines have the new software (if in fact they are implementing that as a rolling change) and which do not.

I did look to see if the 2023 Passport has the new J35Y8 that the 2023 Pilot has, which makes valve adjustment a moot point (its valve lash is hydraulically adjusted). But, that doesn't appear to be the it must be some other reason (perhaps as noted above).
Note also that there's a part number for the software update (in the A23-008 bulletin linked above) for 2023 Ridgeline, but not for 2023 Passport, which further suggests to me that Honda determined this not to apply to 2023 Passport...I'm thinking it must already have the software update applied from the factory, but they didn't quite get it in place for some reason for 2023 Ridgeline.
Yes, it could be the SW change was implemented on the mfg line. I was referring to the valve adjustment warranty extension.
It's not immediately clear to me why, but a prerequisite to the warranty extension is the software update having been applied. So they're not going to give the warranty extension on a particular vehicle unless the software update is applied first. It almost seems that Honda is saying the old software is actually leading to valves needing to be adjusted early. That doesn't make much sense...but that sort of seems to be the way the logic is laid out here.

And if that really crazy notion is correct, and if 2023 Passport already has the new software in the build sequence and none of them were ever built with the old software...that could be why 2023 Passport doesn't have the warranty extension.
I had our 2022 Pilot to the dealer yesterday for this and, so far, I haven't noticed much difference in how often the system will stop the engine. I always disable it if I remember before a drive, and I left it enabled yesterday afternoon on the drive home and running some errands to see if I could tell any difference and, as it did before the software update, it offered to stop the engine for me about every time I came to a full stop (with the message on the screen telling me to press the brake to stop the engine).
I am confused, is Honda saying that if the software update has been applied and your Idle stop still shuts down the car and it wont start again then go back into the dealership for a valve adjustment?
I don't really understand the link between the idle stop issue and valve adjustment, especially since the cars seem to start in park with use of the push button right after the no-crank. Does the idle stop restart while still in drive put an additional load on the system, just enough load that loose or tight valves can cause a no-crank? I guess that's the likely scenario, because the warranty on the valves is extended...I suppose Honda would then perform a valve adjustment on the engine you still experience issues.

After my software update, the Idle stop no longer engages/works, i recently took my car to a independent garage with a Honda certified technician and he said that replacing the battery sensor has worked in his experience on Acura's.
A Honda dealer will have the factory scan tools, and I presume they'd be able to go into the data and see why the idle stop system is not engaging. It sounds like this technician is recommending a sensor based on what he's experienced in the past, but that may or may not fix your car. It seems plausible that it's receiving a signal of a weak battery, which is disabling the idle stop. Is it really a malfunctioning sensor sending that signal, or is the battery truly slightly too low on charge? Again, I presume a Honda scan tool would be able to identify the issue.
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The TSB for the valve adjustment warranty extension states, "...the vehicle may not restart automatically due to excessive cylinder pressure..."
Right. But my understanding is when you put it in park after it doesn't start, and you use the push button to start it, it starts right off and you can drive away. If my understanding is correct, I'm not sure why the idle stop won't start it but the push button will. I would think excessive cylinder pressure would impact either method of starting, and you wouldn't be able to start it at all, right?
What is the idlestopper thingie? how do I get this?
There's a sticky thread at the top of this subforum with lots of information and experiences with different devices:

What I don't understand is why California wants an auto stop/start that stops the engine less often.
It's not that California doesn't want the Auto Engine Idle Stop (AEIS) to work correctly or less often...rather, they want to ensure that cars on the road are up to date regarding recalls and major product updates. This is a safety issue more than it is an emissions issue.

Regarding cars on which the AEIS basically no longer works, I have to think there's an algorithm based on age or miles built-in to the software. We had this product update performed on our 2022 with about 14k miles at the time, and I can't tell any difference. I almost always disable the system to start with, but I drove around with it enabled for some time after the software update to see if it'd engage less, but it doesn't seem to. Every time I brought the car to a stop (after it was warmed up), it'd cut the engine. Like...every time.

But our car is pretty new still. If we drove the car using the AEIS more, and started accumulating more miles, I wonder if it would start to taper the operation some. In other words, I wonder if there's some "glideslope" built in to the software where, if the engine has fewer than 20k miles, then 100% of the AEIS eligible situations results in a stopped engine...and then if the engine has between 20k and 30k miles, then only 80% of the situations results in a stopped engine...30k-40k miles = 60% engagement...40k-50k miles = 50% engagement...etc.

I still don't understand why the valve adjustment impacts only the AEIS, and not push button starts. Why can the AEIS not restart the car, but the owner can when put in P and the push button is used? The only thing I can reckon is the AEIS uses some sort of "low power" start mode where it doesn't give the starter full voltage or current when it tries to start the engine. I don't know why it'd do that if that's really what it's doing. Is it to save battery life for multiple restarts, over and over again? I understand, mechanically, how valve clearance could impact the startability of the engine, but I don't understand why this impacts only the AEIS.
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I took mine to the dealer last Friday to have the update installed on my 2020 Touring. They said they completed it, but as soon as I drove off, the car shut off again at the first stop sign. It has been acting exactly the same as before. Different behavior than others have experience in this thread. Does anyone know if there is a way to check the software revision to see if they actually updated it?
Did you have to sign a warranty and/or emissions statement when you picked the car up? I had to for our 2022 model, and I think it's a pretty sure sign that it was updated.

As I've posted several times, our 2022 behaved exactly the same after the update as it did before the update. It seems like the criteria for engagement may be tighter and/or have some sort of age-based logic, but ours will shut down immediately when coming to a stop, and fires up immediately when lifting off the brake, just as it did before the software update. It seems like most who report the system not working any more have a bit more age or miles on the car and battery, so it may be cutting back the frequency of use in that case.

I did install the Idlestopper this weekend and it works perfectly. It's worth the $89 for me to have the device turn it off reliably, every time. Others have a different opinion on that, and that's okay.
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