Stevenvillatoro.
How is your performance since you got the update?
Greg

 

well, I'm bemused-- my car 'seems to have a mind of it's own' (that's a CVT joke). I tried dropping into S, going up my long hill home last night, and it got regen-happy. Climbed from 4 bars to 7 bars and wanted to keep going, no matter what I tried with the accelerator. So I got impatient and went to D mode, where at least I can control the charge/assist a little better.

But then today on my way in (also up a hill part way), I tried dropping into S, and it kept pulling the same amount of assist as in D mode! Didn't seem to make any difference, aside from a slight drop in MPG (and slight increase in LOD, of course).

So I'm guessing that this is another feature of the HCHII that is highly temperature-dependent; both in terms of how well the car is warmed up (which often mine is not completely) and ambient temp-- is that the experience of other folks? I'll keep experimenting, as I like the concept, but I'm clearly not aware of (nor controlling) an important variable determining when the S mode will help with charging the IMA.

Not boring!

Philip

 

Hi Philip,

I've seen both behaviors too. My educated guess is that in S mode the car starts regen'ing with 2-3 bars if the PCM thinks the charge is too low, perhaps in a conservative guess that the hill might be long, and it needs to store some charge. In fact, I've tried to induce this to prove my theory, and succeeded at times.

If you have really good SOC then the assist bars are almost the same in D or S modes (in my experience) ... which is kinda annoying. I truly wish there was a assist +/1 and charge +/1 button on the steering wheel

Both of the above could also be temp' dependent. Also, don't forget: if you load the 12 V battery, the car tends to trickle charge more often with less assist affinity. For example, if you turn the headlights on after a cold start. --ag

 

I have decided I will never update my 08. It may be a bit over assertive with the assist but with my driving style i keep it over 4-5 bars at all times.

 

In the past three months, I've put 10K miles on my HCH. I did some comparative city driving experiments during the past month (mid-December to mid-January), using the instant fuel gauge as the basis for these particular calculations, since short-interval hand calculations would have been impossible. In this past month alone, I was in San Francisco (hilly), Northern New Mexico (10º temperatures), Phoenix (temperate and flat), and Los Angeles. In each city, my driving routes and other factors were repetitive and nearly identical each day, making it easy to compare daily results using each method. My routes were 90+ percent city driving with very limited freeway or cruising above 50 MPH. Calculations include ICE warm-up times. My only test goal was to compare city fuel economy under two conditions: (1) driving mindfully using simple techniques* described in my recent posts here, and (2) driving conservatively but without regard to any special techniques. Overall, among all cities, I achieved 49.3 MPG by using these techniques, and just 37.6 MPG without the techniques. I found little-to-no difference in results from city to city, i.e., environmental factors such as terrain, temperature, etc., didn't seem to cause much fluctuation in results – driving technique was the only significant influence. With nothing but simple techniques that anyone can do, I averaged 12.7 MPG better. Incidentally, my city results were usually equal-to-or-better-than my freeway fuel economy, especially in the mountains of Northern AZ and NM. These comparisons were done to help me with my own driving style and to better understand what I could expect from the HCH with the new software. I hope it will encourage those who want to increase their city fuel economy, as I did.

By the way, to the best of my knowledge I have never had a recal with my HCH under any conditions; however, in my '02 Insight, I used to have recals all the time. Maybe due to having learned to better manage/conserve the battery assist?

* Also refer to related articles and posts by 'msantos' and 'tarabell' on cleanmpg.com.

 

Thanks for posting your recent experience, Steve. I'm glad to hear you are still doing ok post software update. I have an 05 with 127k. I posted earlier I got an update that took care of check engine codes calling for new 02 sensors and Cat. The lights never came back on. I don't know if the update is similar to the one they do in the 06-09 models. haven't had significant problems with battery pack. My mileage really hasn't changed much. Averaging 42 to 44. Since reading on this blog I have learned some things. One thing was that last week one day I drove to work about 35 miles, and my SOC never came up all the way. It came up to about 75% several times and back down to 50 to 60% at times. When I got to work it looked like around 70%. I put it into park and revved to 3k. It charged all the way up. I lost about 1.5 mpg off my stated mileage for the tank. When I drove home that evening, the mileage went back up over what it was before the extra charge, about 43.5. Is it a good idea to do this periodically if you don't see the SOC coming all the way up? Greg

 

Steve, Thanks for posting this. Can you additionally post two important parameters from the above experiment?

1) How much distance did you drive one way?
2) What was the nominal speed in the 90% city driving situation? 25? 35? 40?
-- Also on average how many times did you have to stop for traffic or stop lights or stop signs?

-ag

 

It would be hard to succinctly answer those questions because of the extensive mileage and variance of trip length and conditions from city-to-city. San Francisco was nothing like Santa Fe which was nothing like Phoenix which was nothing like L.A. Oh yeah, I forgot to include Portland, Oregon in my list of cities. But remember, my goal was only to compare techniques (city driving strategies). In each city, I tried to mimic the routes, speeds, conditions, etc. so that I would have valid comparisons – varying my driving 'style' on alternate days in each city. In other words, if I did short trips one day, I tried to do similar short trips the following day, for example. I did a LOT of city driving... probably nearly a thousand miles. The HCH loves cruising speeds of 37-50 MPH, so I generally targeted those speeds... but San Francisco, Santa Fe, and Los Angeles often won't allow decent city speeds. Therefore, I had to pay close attention to coasting and regen opportunities and use 'S' mode liberally to keep the SOC topped up. I always try to stay out of the lower MPG speed range as much as possible. Phoenix was a paradise for good in-town cruising, where I could effortlessly maintain good speeds (40-50 MPH) on its long avenues, with lots of coasting that kept me at 7+ bars effortlessly. Hope that helps.

 

My Honda only has 14k on it, but it's salvaged which voids the warranty, also it voids any need for any terrible software updates yay. The side effects the TSB lists include, less assist at higher speeds and a couple others I don't particularly like. Also, I can't wait to use the fact that it's smog exempt forever to put a fully electric drivetrain in once the original one dies =) well I could wait at least 100k I suppose!

I figure there will be several electric cars on the market by then, I just like the styling of the honda enough to do it, especially if they keep on the ugly trend which toyota in particular is mired deep within.



P.S. for any used car buyers considering a 06-09 HCH you can tell if this major IMA update has been applied to your car or not by examining the VIN # under the sliding plate which is under the hood. If it has a "punch mark" under the 5th character then it has had the update, if not then no. Hope this info helps anyone who's is looking to buy a used one...