It seems to me the IMA assist is on very seldom. My battery always has at least 3 bars, usually 4 or 5. And the green charge bars light up any time I decel or go downhill. But the blue bars are a rare sight. And when they come on, I haven't figured out how to treat the accelerator to keep them on. I'd think the IMA motor would be on more often to help FE. Any advice on how to get more IMA use?

Very helpful site, by the way. Thanks to all. Love my HAH!

Not really much you can do as it is running off a program with many many variables. Best thing to do to keep the assist going active is to drive around with the ECO light on as much as possible and as long as possible. I've noticed that by doing that the assist comes on more often and stays on until the program realizes that it needs to switch to 6cyl mode for various reasons including uphills, passing, etc... Also while driving with ECO on and assist going try not to let the assist bars go all the way. When it does this it tells the program to switch to 6cyl mode because the assist is still not enough to get the car to the speed you are trying to achieve or maintain. hope this makes sence...basically it takes some practice.

2005 Accord Hybrid 15.65@89.91mph

2003 Lancer Evolution VIII (Sold) 287whp/283tq

it takes a very sensitive foot to keep the IMA bars lit, but not peg it and force it over to 6cylinder mode- I am far frm mastering it.

Generally, I ignore IMA completely and focus on just the eco light. If anything I use the regen just as a light brake, and save the friction pads. On the rare occasions that I punch it or it goes on by itself, that's cool. But I don't worry about IMA. I hold 3-4 bars 99% of the time.

I used to own a Civic Hybrid (5 speed) and now the HAH. With the Civic, assist was very predicable and happened often. With the relatively weak engine, it needed it. With the Accord, I have caught myself a couple of times seeing the assist bars come on then backing off the accelerator a bit, I guess in an unconscious attempt to save a little gas or something. I'm trying to break that habit, and now I'm seeing more assist. The Accord's use of assist is much more limited than the Civic's. The Accord uses more of the battery power to power accessories (especially A/C) when the car is stopped than the '05 and older Civics, so the battery power is still be used.

Thanks- a perfect side-by-side comparison from someone who knows both flavors of the Honda system! Good point about how the battery pack still helps save fuel (electric AC), even if not directly making the car go.

The dominant fuel saver for us is VCM. Always will be. Keep the eco light on!!

From what I understand the IMA motor is being used (without showing assist bars) during VCM to 'balance' the engine so that it doesn't shake as much as it would if there was no IMA, so during VCM there's still some battery power being consumed (minimal, just pulses) to help the fuel economy.

Assist is not the holy grail of fuel economy, really it's everything else that gets you great fuel economy, especially VCM.

2001 Prius Photos       2005 Prius Photos
'97 Prius Simulation Prius inner workings

hmm. I hadn't heard that anywhere. Interesting, though. I'd just assumed they were using piezo devices in the engine mounts. I suppose that if the IMA were providing small impulses when the other cylinders would have been on their power strokes could smooth out the motion, though. Anyone know for sure?

In the Insight, a 3 cylinder car, the IMA is used at idle speeds to smooth out the inherently rough idle of a 3 banger. I don't think the HAH will idle in 3 cyl. mode so I doubt the IMA is being used in that manner here.
The Insight also has fluid filled engine mounts to dampen the vibrations.

thanks. I hadn't thought of fluid damping either.

I think you may be right that IMA does not act as a counterforce, even in 3cyl. After all, the Odyssey also has VCM with almost the same engine (though upscaled) as the Accord, and it does not have any IMA.

PS- welcome to greenhybrid! Great to have another multiple-hybrid owner. I think you're the only Insight/HAH owner here- Xcel and others will no doubt be very interested in your observations.