I have experienced the same bizarre effect since the IMA software update. On perhaps two occasions I noticed the number of pips on my SOC guage increased from four or five to the max of eight. Ironically I used to see my SOC drop suddenly with the old software, and now I'm experiencing the opposite effect!

 

The fellas at cleanmpg explained it here. they call it "hidden regen" and these updates make more use of it.
I called my dealer to have the flash done to my hch tomorrow.

ks

 

whats wild though is he got increase in charge while using assist. I've had hidden charge in all 4 variants of software in my car while cruising on level ground, but never while using assist. very weird.

What I have had that sound similar, and many times here recently after this update is a total battery crash down to 0 or 1 bars, slow recharge up to 6 bars while driving with no assist, then suddenly assist is available and the charge suddenly fills to 8 bars like the ecu realized it slammed to the top of the perceived charge of the battery pack.

I have to wonder if what is happening is a small set of deteriorated cells are holding back the full capacity of the pack, and the perceived max is being hit based on some new thresholds in the software before ALL the cells are full, then the ecu says "pack full, i'm done charging" to protect the life of the pack, then providing diminished usable capacity...at least in my case.

Battery pack is "protected". It will last longer, but at what cost?

 

Hi Kids,

Lots of speculation about charging sequence here, but no mention of how this update effects MPG. The update has been around long enough that one of us must have some decent data on fuel consumption. SOC is fine but at the end of the day we are all about the mileage. I have resisted this update due to all the disparate reports. It seems that Honda may be in corporate protection mode rather than product improvement mode with this software update. I have no complaints with my current (original) flash. Steven, Mendel, all, what is the net effect of this flash on your mileage?

 

Just reviewed my mileage monitor logs on my Pre now that I have three fill ups post update:

I've I seen a 10% degradation in mileage for me post this update. I was getting 35-36 city driving before the update in the heat. The next fillup was the day after my software update, lasted for 2 weeks, and I averaged 33 mpg city. Measurements are by fuel mileage divided by fuel added.

On pure interstate driving (70+ MPH): 41 with one heck of a tail wind, then 36 without the tail wind, both in hot weather again. Last year I saw 45 easily with that strong of a tail wind and 40 without in the same situations, so similar, but estimated 10% drop in the heat.

 

Okay, Hybrid Captain... I did some math for you. I compared my fuel economy before and after the upgrade. Note that I've only driven three tankfuls so far since the upgrade. Here are the results:

Pre-upgrade average MPG: 39.39 MPG (six tankfuls)
Post-upgrade average MPG: 44.14 MPG (three tankfuls)

My fuel economy has increased by a whopping 4.75 MPG, or about 12 percent!

But there is another factor at play, since I had an oil change done at the same time as this software upgrade. So I went back and researched my previous MPG when I had new oil installed, and found that I had averaged 40.2 MPG, also based on six tankfuls. Therefore, I expect and do believe that I am getting significant better fuel economy and performance due to the upgrade. The day-to-day benefits, for my driving style and conditions, have been exceptionally worthwhile and pleasantly dramatic, with no apparent downside whatsoever. Since this car was new, I have never averaged such good fuel economy this consistently or effortlessly.

Hope that helps, and that your results may be as good. YMMV!

P.S. All my fuel economy data was calculated manually, all fills done at the same gas station, and all tankfuls were based on comparable driving style and conditions.

 

man, i need to get my car back in, was going to do it this afteronoon, but my wife just took my son to the ER for a possible broken toe! I want my civic hybrid to be the one with the bigger M P Gs!

 

I am seeing 5mpg loss and much less assist from dead stop unless I really mash the pedal. The battery has not completley drained as it was doing prior to the update. I guess this was the intent of the update. It has been extremely hot where I live and I only hope I see much better results when the weather cools off. I am not a happy camper right now though.

 

Wow, this is so confusing, Kenny & Jason are exeriencing degraded performance after the update, many, myself included are feeling the car is improved.
Could your updates have been installed wrong? are your batteries failing? did they tell you they installed all the updates and forgot this newest one? I don't know but something is wrong.
I am experiencing about the same mileage, that is to say, for 100% city driving I am showing about 44 mpg, a/c on 100% of the time (72 degrees) with outside temps in the 80's & 90's and all driving before sundown so the a/c is fighting the sun (my car is the dk. blue)
I am not experiencing the daily re cals I was getting in hot city driving, I have seen it drop to 3 bars 2X but go back to 4 within seconds.
My driving rarely sees speeds above 40 (none on this tank) I rarely exceed 2,000 rpm on acceleration, I see assist below 30, even when down to 3 bars.
I did fill the tank the same Saturday I got the software, so I am still on my first post update tank (about 200 miles), I am finding one thing odd, pre update, when I reset my mileage I would see mpg as high as 60 for the first 100 miles, then a steady decline to about where I would expect for the conditions....this tank started in the 30's and has been stedaly climbing to the mid 40's...will be interesting to see if the mpg is more accrate I was showing about 3% low but according to my gps, the spedo is right on.

 

Hey Bob,
I just don't know...every time I take my car in I harass the service adviser if they do a test on the batteries beyond just checking to see if the IMA light is off. Only thing I've been told is honda doesn't give them much more then that to work with. My sister-in-laws 07 HCH II has like 10 or 15,000 more miles then I have and is running fine...i've always been able to hop in her car and achieve better mileage then mine. I'm going to try to get it in tomorrow, but I'm doing consulting in topeka next week and don't really want to put the miles on my camaro that only gets 19mpg. Maybe time to throw down with Service advisor and argue for the rental my extended honda warrenty is suppose to give me even if all his loaners are out.

Just had another battery crash tonight at a stop light. Autostop was on, electric A/C running, it ran down to 4 bars, then ICE started and SoC dropped to one bar and I didn't even have "emergency" assist to get going again. I had filled up this morning and driven approx 30 miles and I'm only at 31 mpg for the day so far combined city/highway. Today was another 100 degree day, but the heat is no friend of mine or my car for sure!

Giggles and grins, i uploaded a pic of my crash tonight, then a pic of a crash post update, then within a few miles the car deciding the SoC was suddenly full.