Wow, the battery DOES make a difference! (Insight IMA back on after forced recal.)
 

Thanks to Jamesqf's tip, I forced a recal on the computer by pulling fuse #18 (5th from the left, bottom row, very important info lol). As soon as I started the Insight it showed charging on the dashboard! I drove around town a bit and the battery level kept on rising. The auto stop kicked in and scared me, I thought I had stalled it somehow! The idle also dropped under 1000 rpm. Once it had some charge in it, the battery assist also kicked in when I was pulling away from a stoplight. What a difference! Man it's pretty peppy now, it's way more fun to drive. I figured the assist was only for hills or passing, I didn't realize it kicked in at low speeds as well. I have yet to see how long the battery will last when climbing a steep hill, but at least I know the charging system works, and I have had no lights come on the dashboard to tell me there is a problem anywhere. I was so excited I drove to a local big box store and bought a cassette adapter for my MP3 player so I can rock out through the factory Honda cassette deck. Good times!

care to explain a bit more about what you think was going on and the problem you fixed?

Sorry, I had that in another post. The battery was showing 1 bar on the charge display, and the car wasn't charging it. It was also idling too high, and the auto-stop wasn't kicking in. Pulling the fuse fixed all of those problems, so now I can figure out if the battery pack is any good.

I'll trade you my factory Honda single-CD player radio for your cassette radio. :D

I'd rather have the ability to use the adapter. (Do the FM transmitter thingers work any better than the cassette adapters?)

Glad to hear your forced recalibration worked.

My pack is in bad enough shape that the IMA light and battery-related Check Engine Light codes came back (and the hybrid assist/regen disappeared) after only about 30 km or so after I did a forced recal.

I don't mind the way the car drives without the hybrid "boost". I'm used to Metros/Fireflies :).

If you want one, I think I still have the old one from mine on a shelf somewhere.

Actually it's a lot more for the low-speed acceleration than anything.

On hills, a good battery should let you do maybe 1000-1500 vertical ft at about 6% grade, doing 55 or so. (Of course this is really approximate.) Couple of points to note.

First, you may see a gradual drop of the charge gauge to part way down, then rapid drop to zero. This is a less-than-perfect battery, but should still give you decent service for years.

Second, there's a bit of a trick to keeping it from using too much assist on a long climb. You want to avoid getting SOC so low that it forces regen while you're still trying to climb. You can climb at 50-55 mph in 3rd, but it's good to keep the RPM below 3000, because that's where the VTEC shift point is. You can feel it kick in, and see a drop on instant mpg. You can cruise in 4th at highway speeds too...

Metro, I find the cassette adapters work better than the FM transmitters. Some work better than others, price doesn't seem to have much to do with it. I bought the cheapest one they had at London Drugs and it works great. I will be looking for a cassette deck for the other twin, it has some fancy Sony CD player with no MP3 input in it, and man I hate aftermarket stereos.

Well the battery assist experience was short lived, it charged all the way up to full, and the assist would kick in for about a half an hour. Then when I went out later that night, the pack was down to 1 bar and it wasn't charging again. I'll try a recal again and see what happens.

Just FYI, if you're planning to refurbish your own pack, doing forced recalibrations and using regen/assist on its ailing cells will further damage the weak ones. (More of them may need to be replaced.)

Having said that, I wouldn't hesitate to recommend to any ecomodding type person to buy an Insight with a dead pack, and not bother replacing/refurbishing it. Just use the car as a non-hybrid. As long as the DC-DC converter works to keep the 12v system happy, you can drive it without any of the other IMA functions active and still achieve stellar fuel economy.

I actually see no real reason to refurbish my pack and bring IMA back online, aside from sheer curiosity about the project itself and then getting to play with the hybrid functionality.

I think this is a good idea but a better one might be to look at alternate pack designs. It sounds as if the stock battery management system may have a systemic problem and analysis might lead to a pack with longer legs.
I am not a Honda IMA expert but I remember seeing a Honda chart showing how the electric motor provides low-end torque. What I don't know is the extent the Honda control laws stress the batteries. Monitoring the temperature would be a good start.

You've got a vehicle with outstanding, low aerodynamic and rolling resistance. Bringing the ICE back to OEM spec seems like a natural especially if it can be done in a way that extends the battery life.

Bob Wilson

You're absolutely right about the torque benefit of the electric assist - it peaks at 2k RPM, engine+motor.

But a "neutered" gen. 1 Insight is still a step up from my usual ride, in both fuel efficiency and driveability. Even without assist, the stock Insight has more power, not to mention lower rolling resistance, less aero drag and better handling than a stock Metro/Firefly.

I have to agree with Metro, an Insight with no battery assist is still decent to drive. I was a little disappointed to find that the battery was done in mine, though for what I paid for the car, what could I have bought that was even close to it? A sort of rusty CRX would have cost me more, and wouldn't be as fun. The build quality on these cars is impressive, mine has a lot of KMs on it but hardly a squeak or a rattle out of it. The steering is fun, and it's just plain comfortable. Now I wouldn't take it on a long trip through the mountains without the assist, but I think I will keep it as my daily driver for the summer at least. The super hot coug - I mean nice lady that lives in my building saw it and said it was cool and she loved it. Honestly that was reason enough to drive it right there ha ha.

Until I get the input shaft bearing sorted out on the other twin, I won't be able to drive it and see how the battery pack is in it. So for now, I think I will try to make this one as driveable as possible the way it is. Without the assist I find there is a flat spot once you just get moving from a stop, that will be the first thing I try to sort out. The return spring on the accelerator on mine seems awful stiff, it's probably meant to be that way, but even softening that up would help push past that flat spot I think.

What I'm trying to suggest, perhaps not so artfully, is think of the motor as another 'performance' part of the engine no different than a special cam, ignition, fuel or exhaust system. We are so used to dealing with mechanical parts that we are resistant to the idea that electro-mechanical systems can make major improvements in engine and vehicle efficiency.

How many times have we seen folks propose just adding a motor to their car for a home-brew hybrid without taking a systems approach and understanding 'you can't bolt on high mileage.'

What I'm suggesting is if you have a system already designed to use the motor . . . well not using is a bit like having one dead spark plug in a four cylinder engine and not fixing it. You'll get to where you're going but you're carrying a lot of 'dead weight' and not getting any good from it.

I don't mean this in a hostile way any more than when I'm sitting in traffic, my engine is off, and I hear the car next to me needs a valve job or the pickup with the loose fan belt or the van with the stuck choke. These folks have lives and immediate concerns so car maintenance is down on their list of priorities. Just I'm trying to gently suggest the time to fix the roof is before it rains and we're about 3-4 months away from 'cold weather.'

Is it that hard to pull the Insight battery pack out and at least put it on the bench? This would be fascinating thread to watch and to the limits of my ability, perhaps even offer some help with either suggestions or parts (mostly Prius but who knows.)

Thanks,
Bob Wilson

I don't disagree (entirely) Bob.

But with my "hobbled" Insight returning 80-95 mpg (US) in my current driving regimen, I believe *in my case* repairing the pack and bringing the hybrid functions back online would be a textbook illustration of diminished returns! I'm pretty sure even the low/moderate expense of refurbishing the pack couldn't be justified from a strictly financial/fuel saving angle.

Why? Because I have modified my driving style to mimic the major fuel-saving benefits of the IMA system.

In city driving, I'm manually killing the engine when coasting/stopped - actually, I'm more "aggressive" here than the IMA system would be on its own. And on the highway I monitor my right foot very carefully (and modulate load) to maintain lean burn as much as possible, which is how to get stellar highway fuel economy from this car.

A less motivated driver would be relying on a functional hybrid system for idle stop in the city and to keep the engine in its lean burn envelope (or "widen" that envelope) on the highway. For that driver, a pack repair would be a much more pressing concern (and probably more easily justifiable from a financial angle).

Again, I do plan to pull the pack and investigate refurbishing at some point. (Just not in the immediate future - too many projects!)

Darin, explaining why hybrids are not necessary in the hybrid forum is going to be a hard sell :)

How much does the battery weigh? You might yank it out for now just to save a few pounds if for no other reason.

In my case! In my case! :D

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"The battery is manufactured by Panasonic EV Energy and weighs only 48 lbs. or 22 kg." - InsightCentral.net - Encyclopedia - Honda Insight Battery Module

MetroMPG you've got it exactly right. The best way to efficiently use Honda's IMA system is to not use it (for acceleration, at least). I use a switch to disable assist at least 90% of the time. I do allow regenerative braking when I need to slow down and I prefer auto-stop to turning the car off. I also like the quiet engine start using the motor rather than the starter.

You probably would still get better mileage with a healthy hybrid battery. Your 12v battery would be charged from the hybrid battery instead of the electric motor like it is now which is causing some additional load on the engine and may be causing it to be a little harder to get and/or stay in lean burn. I'm also unsure of the service life of the insight's starter, my car used its starter twice last year. Both times the temperature was below zero (farenheit).

Of course a "typical" driver would do none of these efficiency enhancing driving techniques or mods, so a fully functional system would be to their benefit.

But you're right - one of the first mods I'll do after fixing the pack will be installing the clutch switch mod to shut it all off again :D ... well, to disable assist most of the time, as you say.

Of course, sometimes you just can't coast to decelerate, in which case regen will be most welcome (as will be the max-regen switch mod). I will say I definitely wish I had regen every time I have to hit the binders while driving this car.

EDIT: and you're right - that quick, quiet IMA engine start is pretty slick compared to the archaic 12v cranker.

I don't believe that will work (though I don't know of anyone who's actually tested it). It's the systems design thing again: the IMA system is the alternator, and I believe needs the battery pack - even a "dead" one that doesn't give good assist - in there as sort of a ballast for the system.

Another thing you may not appreciate is that the motor is also controlled so that even when it's not providing assist/regen, it's still using a small amount of current as a vibration damper.

FWIW, pulling the battery is not all that big a deal. Took me a couple of hours the first time. A cordless drill comes in handy, though, as there are dozens of small bolts holding the cover on. Also, wear insulated gloves, as the battery does produce enough voltage to kill you if you happened to create a short. This isn't easy, but why take the chance?

It was just a suggestion. Like you, my project list is much longer than I have hours in a day to keep up with. When you're ready to tackle the electric power side, you'll have a lot of help. <grins>

Bob Wilson

Thanks, Bob. I have a feeling mine will just be one more of several pack refurb projects on the site.

Matt (Robert Smalls) has already nicely documented the rebuilding/rebalancing of his Insight's pack: http://ecomodder.com/forum/showthrea...ems-13610.html