CPO Honda w/ transmission pulsation - dealer can’t diagnose - sell or keep pushing for repair?

[VTECOverRated]

And i assume these are wet clutches?

When we were considering a civic hybrid (err sorry insight) i understood that the engine never drove the wheels directly, perhaps i misunderstood.

To the OPs problem, i would defiantly keep darkening the Honda dealers door, but i would scan it to see if there were codes. I might consider a fluid change in the "transmission" if that's a thing.

Drive Force Transfer
Just like the previous model, the Accord Hybrid is not equipped with a conventional mechanical transmission. Instead, motive force transfer is accomplished through the interaction of the Accord Hybrid's gasoline engine and two electric motors. Coordinated by the IPU, this form of drive force transfer offers smooth and predictable acceleration matched with efficient low-rpm highway cruising when the gasoline engine is in operation. Gasoline engine shutdown is seamlessly integrated into the operation of the Accord Hybrid when appropriate.


The drive force transfer system operates without the need for a torque converter, mechanical pulley or belt. It instead uses two motors for driving and generating power. The system is optimally and rapidly able to control both engine and electric motor rotation in order to deliver higher fuel efficiency and quicker engine response in each driving mode.


When cruising at mid- or high-speeds in the high-efficiency range of the engine, a lock-up clutch is engaged, connecting the drive motor to the generator motor to transmit engine torque directly to the drive wheels as efficiently as possible. In EV Drive operation, when the battery-powered drive motor is used for either acceleration or regenerative braking, a clutch disengages the stopped gasoline engine from the drivetrain to eliminate efficiency loss from mechanical friction in the engine.


Improving efficiency and reducing weight and size, the drive force transfer system of the second-generation i-MMD integrates the torque limiter within the flywheel.

Source: https://hondanews.com/en-US/releases/2017-honda-accord-hybrid-press-kit-powertrain

 

[avacado11]

How long ago did you swap the wheels and tires back to OE? Did you disconnect the negative battery terminal and allow the ECM to relearn the change back to OE tires? I'd be giving that a shot.

I had the wheels swapped on some time early April. It did fine for 3 weeks. I took it in to Honda about 3 weeks after the issue started, they inspected and said it was the wheels. So it rode on those wheels for a total of 6 weeks before I took them off.

I ended up replacing the 12v battery a few weeks ago after it died on me randomly. I also figured maybe it was a weak 12v causing it. Guess not as the issue still exists

 

[avacado11]

They cannot work simulatneously.

And I believe the issue is they are trying to work simultaneously, and the ECU is preventing it which in turn makes the engine engage/disengage constantly

 

[demarpaint]

I had the wheels swapped on some time early April. It did fine for 3 weeks. I took it in to Honda about 3 weeks after the issue started, they inspected and said it was the wheels. So it rode on those wheels for a total of 6 weeks before I took them off.

I ended up replacing the 12v battery a few weeks ago after it died on me randomly. I also figured maybe it was a weak 12v causing it. Guess not as the issue still exists

It's then safe to say you ruled that out. Going to a different size tire can cause problems though.

 

[avacado11]

This 2 motor drive system has a clutch based transmission. Does this happen when in park? If not, the clutch(es) are probably slipping. If that isn't the issue, most likely it needs the fluid replaced, as its not engaging the clutches properly.
This is why I dislike honda's hybrid system's. Unnecessarily complicated compared to toyota's gen 3/4/5 system's.

Either way, push for repairs, if its under warranty, contact corporate. Record all conversations using your phone, make sure you have everything on record. Give those scummy honda dealers a reality check.

Just as an FYI, at cruising speeds you will be using more engine than electric motor. Honda's system is designed to be used in stop/go traffic and cities where speeds are low. The motor's torque falls off a cliff past 45 MPH.

Nothing in park. Honestly nothing above 60 and nothing below 40.

 

[avacado11]

Scanner? Codes?

No codes at all from my standard OBD 2 reader. I don’t have a clue of what consumers can buy that is Honda specific software. I have Forscan for Ford have not been able to find the equivalent for Honda.

I am highly considering replacing it with a Ford since I will be able to diagnose it should the dealer be unwilling/unable to

 

[VTECOverRated]

I know my ktuner will read codes and data log. But thats a lot of money for just a reader.
Since youre saying it happens between 40 and 60, this does sound like a hand off issue, as this is where the hand off happens. Could be a fluid thing, since according to honda, you should change the hybrid transmission fluid at 47,500 miles (ish) in "adverse conditions" so you are nearly double that.
Honda transmissions are honestly like this. They start doing random weird crap until you change the fluid then voila, its like new, and then after another 30-50k miles it starts up again. Every honda I have had is like this, and it sort of annoys me, but I change my transmission fluid on all other cars even if there are no issues.

 

[KrisZ]

Changing the fluid is probably a good idea, followed by warranty and if that doesn’t work, dump it.

 

[t1snwrbrdr12]

If you can make it happen, you may just need to insist to take someone there for a ride (tech, foreman, service manager).

 

[SeaJay]

Dump it just before the warranty is up.

Find out how much the dealer who has been working on the car is willing to pay for it. That should tell you something.

 

[SC Maintenance]

Maybe dealer saw something first time in their diagnostic software that might indicate tires. Now that tires are swapped, return. Have them scan it again. Maybe they can reset the controller, I am guessing its some version of a learning transmission, most are now days.

Alternate - change up your driving style. If you are a light peddle driver, try a heavier pedal for a few days - see if it changes. If your heavy pedal, try light. If its in the self learning control that might still be affecting it.

A regular OBD reader won't give you anything but emissions/engine. You can get a Transmission reader - preferably two way, but I have no idea if it will work for you. The Honda specific boards might be more help on that.

 

[walterjay]

Not your problem. Take it in for warranty repair that you already paid for. It is their problem.

 

[KrisZ]

According to what I’ve observed on the dash essentially the powertrain is having issues jumping back into EV mode/shutting off the engine at cruising speed.

Since the issue is hard to replicate but can bees seen on the instrument cluster, I would take a video of it happening. Or get someone to help you while you drive.

 

[zzyzzx]

I don't see anything that's going to resolve this without being able to read and record live data to find an anomaly or intermittent fault. Or you just keep driving it and hope it gets worse enough to find.

 

[mrsilv04]

Unfortunately, the first mistake was taking it in with the non-OEM wheels/tires on it, complaining about a driveline issue. They were given a the easiest excuse to blame the wheels and tires, and dismiss the complaint.

And it very well might be just me, but I don't think that I'd be changing around anything on the drivetrain of a hybrid vehicle... ever. Too many variables.

 

[HangFire]

I would say this is untrue. Realize your talking about a electronic control of an analog device - an engine and motor. Possibly the tuning worked fine when everything is new, but once you get some wear in the system the transition times or whatever are no longer working.

Not saying this is your problem, just saying your working with system control, not a video game that is purely digital. Realize many times when firmware updates on cars are made its not because the original code had a bug, but to accommodate a mechanical difference that was not anticipated.

Of course this could have nothing to do with your problem.

Either way, its the dealers issue under warranty, not yours.

I agree. Cosmic rays flipping EPROM bits, degraded/defective RAM in a hot environment, random failure. Hardware fails randomly, too. Had a desktop CPU just die one day, M/B worked fine with another CPU, CPU didn't work in 3 other M/B with the same CPU socket... just sudden death. Random stuff happens.

 

[avacado11]

UPDATE

Called dealer and was able to get an SA familiar with my car. He said it is normal for the powertrain to jerk during the power change over, and recommended a transmission fluid change since service records never showed it being changed before.

I have it scheduled in 2 weeks and will update this threat to see if it does anything. Hopefully it fixes the issue

 

[The Critic]

UPDATE

Called dealer and was able to get an SA familiar with my car. He said it is normal for the powertrain to jerk during the power change over, and recommended a transmission fluid change since service records never showed it being changed before.

I have it scheduled in 2 weeks and will update this threat to see if it does anything. Hopefully it fixes the issue

ATF should have been changed at least once already, possible twice.

 

[SeaJay]

ATF should have been changed at least once already, possible twice.

Is the manufactuer's recommended ATF change interval as low as every 35,000 miles?

 

[The Critic]

Is the manufactuer's recommended ATF change interval as low as every 35,000 miles?

Or lower. Recent Honda 6AT's are as low as 25K now.