2006 Honda Insight MT Build Thread

[iikhod]

Probably a lot easier to connect on the outside/over the intake pipe. Aluminum tape might be just enough.

[Ecky]

I don't know that one is better than the other. Depends on what the snorkel and other intake components past the air filter actually do, which I don't know.

[mpg_numbers_guy]

Long post warning.

Went ahead and installed a coroplast lower grille block on the Insight. Used two zipties on either end. Size of coroplast sheet was 4" x 32" for reference. Due to 4" being slightly too tall to fit flush, there are small half-inch gaps on either side of the grille block where air can come in, but I'm fine with that.

I removed the upper grille block for now. Will reinstall it when it gets cold enough to run a full grille block.



Considering painting and gluing in a red coroplast disc over that gaping tow hook hole. Already will be getting the red paint to touch up the bumper. According to Insight Central there's a certain kind of paint (Rustoleum brand I think?) that very closely matches the Insight's Formula Red, so I'll be getting that soon. The OEM part is ~$25 to replace including shipping () unless my dad can get a parts discount from the Honda dealership he works at. Seems a bit much for such a tiny bit.

Brakes developed some "lot rot" from sitting for about 3 weeks, so I drove fast and used the mechanical brakes to loosen them up. They're about 80%-90% better now. Got just under 50 MPG driving like that plus almost completely depleted the battery from using it hard and doing almost no regen braking. Very inefficient driving but necessary to loosen up the brakes and get good mileage from here on out.

Had a CEL pop up - P0420, catalytic converter issue. Cleared it and it never returned despite driving about 30-40 more miles. Will see if I can take out the cat, clean it, and spray it with heatproof paint at some point.

Drove it at 80 MPH on the highway towards the end of my brake clearing run to clear up the last bits of lot rot, and was pulling 50 MPG at 80 MPH. Very impressive I'd say.

Correct me if I'm wrong, but the Insight's most efficient speed seems to be 47-52 MPH, where I can consistently get at least 105 MPG on flat, windless cruising, and 45-55 MPH where I can consistently get at least 95 MPG on flat, windless cruising. That's with the lower grille block, but missing aero panels (will be ordering Scott's belly pan).

Also got the battery charged up during the last run. As it was when driving my mom's Prius, I need to learn to trust the hybrid battery system more. It seems that the hybrid battery performs better and stays charged better when I just let it do it's thing instead of trying to maximize its efficiency. Could just be me not knowing how to do it yet though.

Upshifting at 2200-2500 RPMs seems to yield better fuel economy than taking longer to accelerate by upshifting at 1800-2100 RPMs. In other words, I got about 25 MPG higher from upshifting at 2200-2500 RPMs and driving at 50 MPH than from upshifting at 1800-2100 RPMs and driving 35-40 MPH. It's also easier to maintain a constant throttle position at 50 MPH than 40 MPH and under. Maybe I don't need cruise control.

Also added a warm air intake. Originally bought 4" dryer ducting, but it was too large (I have AC, so some of the wiring takes up some of the space in the normal WAI routing path). Bought 3" ducting and it worked fine. Had to reshape it in the area where it ran by the side of the engine, but it works. Crushed the end of the ducting against the original intake opening and secured and sealed using Tyvek tape.



The area to the upper left in that picture is one of the only slightly rusty pieces on the car. Several of the bolts are rusty, but other than that it's clean. Hoping to get some of the heatproof black paint and paint the pieces after cleaning the rust off of them sometime.

I took some black mesh and attached it to the other end of the WAI, since that opening just looked to invite debris into the intake. Used Tyvek tape again to secure the mesh along with a couple zip ties. Used a couple more zip ties to attach it to a conveniently located plastic tube of wires and pointed the end at the catalytic converter.



And the final product:







Can't say if it improved anything yet. Installed it more for faster warm up and heat retention when colder weather arrives.

More things checked off the Insight to do list. Got almost 4 more weeks to perfect this thing before returning with it to college.

[mpg_numbers_guy]

I guess fate meant it that I am to bypass the battery earlier than expected!

Drove the Insight for exactly 70 miles today. After the first 10 miles the IMA light came on, and stayed on after clearing it 3-4 times. Not getting any assist, regen, or autostop as expected.

Driving without the IMA isn't as bad as everyone seems to make it out to be. I just shift at 2500-3000 RPMs instead of 2000-2500 RPMs. My MPG is the same. Averaged 69.3 MPG over all 70 miles, which is pretty normal. Tank is at around 65 MPG (this includes my fast driving and braking to clean the lot rot).

Grille block helps with warm up, but my warm air intake apparently was a failure - intake temperature stayed at 60 degrees Fahrenheit for half the trip and struggled to get higher. Maybe I accidentally created a cold air intake since I've read that 110-130 degrees is ideal for intake temperature. The air intake is about an inch to an inch and a half away from touching the catalytic converter. Considering making it touch the cat this time. Also, I have no engine bay belly pan yet, so a lot of cold air is coming up there.

So, I will be bypassing the IMA as soon as possible. I am already offered $500 for the battery core by a company to be refurbished, which I will go with unless one of you guys wants it for $600 or whatever. The IMA light just came on and it probably could be grid charged easily back to full health, but I just don't have the time for it, nor do I care to invest the money into a decent grid charger. I was already planning on bypassing the battery when it began dying. Bypassing the battery will let me:

• Lower the floor for more storage space like Ecky did
• Remove about 100lbs (?) of weight from the car
• Possibly install Scott's rear springs, modified to lower the car back to it's original height from it being raised due to the hybrid battery being removed
• Drive the car anytime without worrying about a hybrid battery condition
• Have more fun driving the car -- actually, yes. Throwing the car in neutral and coasting to a stop is less tedious than downshifting through the gears to regen, and I don't have to constantly worry about keeping the hybrid battery charged enough to prevent forced regen. I had more fun hypermiling the car like a normal car and still getting phenomenal fuel economy. No more back-of-the-mind worrying about the hybrid battery condition.
• Recover some of the money spent on the car. Selling the battery core for $500 will make the overall price of the car $1000 instead of $1500.

Bypassing the battery will save me the effort required to wire up 1) regen button, 2) FAS button, and 3) IMA calpod clutch button mods. Instead I will "just" have to wire up a kill switch.

...but does the Insight still track distance/fuel economy with a kill switch???

[mpg_numbers_guy]

Did a little research, and apparently I can bypass the IMA and keep the DC-DC converter just by unplugging the BCM and leaving the battery installed.

Link for reference: Honda Insight (2000-2006) - Battery Bypass Instructions

Will this still keep the 12V charged? It sounds like it should per research in Insight Central..

Also, will the CEL and IMA lights still be on with the bypass? I was still getting lean burn with the IMA/CEL lights on today. Lean burn is a non-negotiable must have. Having the IMA/CEL lights off is a bonus. If lean burn won't work with the bypass then I'll have to see if I can shut the lights off by spoofing something.

Ecky you said you lost lean burn with your bypass? How and why? Did you ever get it back?

Going to try the bypass tomorrow..

[Ecky]

Originally Posted by mpg_numbers_guy

Correct me if I'm wrong, but the Insight's most efficient speed seems to be 47-52 MPH, where I can consistently get at least 105 MPG on flat, windless cruising, and 45-55 MPH where I can consistently get at least 95 MPG on flat, windless cruising. That's with the lower grille block, but missing aero panels (will be ordering Scott's belly pan).

This reflects my experience. 55mph is without a doubt worse than 50. I've found that I can get 100+ while cruising at lower speeds, but it seems like head-winds, hills, and things which interrupt steady-speed cruising affect the car more at lower speeds.

Originally Posted by mpg_numbers_guy

Upshifting at 2200-2500 RPMs seems to yield better fuel economy than taking longer to accelerate by upshifting at 1800-2100 RPMs. In other words, I got about 25 MPG higher from upshifting at 2200-2500 RPMs and driving at 50 MPH than from upshifting at 1800-2100 RPMs and driving 35-40 MPH. It's also easier to maintain a constant throttle position at 50 MPH than 40 MPH and under. Maybe I don't need cruise control.

Those shifting points do not reflect my experience. I find shifting below 2250 delivers the best numbers, but our driving conditions may be different and you almost certainly have newer computers than are in my car. However I do find it easier to maintain throttle at 50 than at lower speeds

Originally Posted by mpg_numbers_guy

Drove the Insight for exactly 70 miles today. After the first 10 miles the IMA light came on, and stayed on after clearing it 3-4 times. Not getting any assist, regen, or autostop as expected.

Driving without the IMA isn't as bad as everyone seems to make it out to be. I just shift at 2500-3000 RPMs instead of 2000-2500 RPMs. My MPG is the same. Averaged 69.3 MPG over all 70 miles, which is pretty normal. Tank is at around 65 MPG (this includes my fast driving and braking to clean the lot rot).

Sounds like you had a catastrophic cell failure - one of them died in a way that could short out the pack, so it disconnected it entirely. Many packs die very gradually instead. Sorry to hear it happened.

Good fuel economy though, considering the conditions!

Originally Posted by mpg_numbers_guy

So, I will be bypassing the IMA as soon as possible. I am already offered $500 for the battery core by a company to be refurbished, which I will go with unless one of you guys wants it for $600 or whatever. The IMA light just came on and it probably could be grid charged easily back to full health, but I just don't have the time for it, nor do I care to invest the money into a decent grid charger. I was already planning on bypassing the battery when it began dying. Bypassing the battery will let me:

• Lower the floor for more storage space like Ecky did
• Remove about 100lbs (?) of weight from the car
• Possibly install Scott's rear springs, modified to lower the car back to it's original height from it being raised due to the hybrid battery being removed
• Drive the car anytime without worrying about a hybrid battery condition
• Have more fun driving the car -- actually, yes. Throwing the car in neutral and coasting to a stop is less tedious than downshifting through the gears to regen, and I don't have to constantly worry about keeping the hybrid battery charged enough to prevent forced regen. I had more fun hypermiling the car like a normal car and still getting phenomenal fuel economy. No more back-of-the-mind worrying about the hybrid battery condition.
• Recover some of the money spent on the car. Selling the battery core for $500 will make the overall price of the car $1000 instead of $1500.

Bypassing the battery will save me the effort required to wire up 1) regen button, 2) FAS button, and 3) IMA calpod clutch button mods. Instead I will "just" have to wire up a kill switch.

...but does the Insight still track distance/fuel economy with a kill switch???

I doubt a grid charger would bring it back based on how it went. You could probably pull it apart and try to find the cell that died, but this isn't a long term solution - any replacement cell would likely get out of balance more easily and would need to be balanced regularly.

Nice to hear you're getting as much for your failed battery! That's a very nice car you have for $1,000. Since you don't live in such a mountainous region you may not see any hit at all without the battery.

I think the car handles better without it personally, and you may not need Scott's rear springs since simply removing all that weight from the back will stiffen the rear up somewhat. You'll need to cut the rear springs a little if you want to keep the same ride height in the back. If you ever decide to go with a new pack or make the car a plug-in hybrid with a small lithium pack (150+++ mpg) I still have my uncut original springs which you're welcome to, and they're quite easy to put in.

And yes, the car will still accurately track economy with a kill switch, it's only if you key-off to turn the engine off that you'll get inaccurate numbers.

Originally Posted by mpg_numbers_guy

Did a little research, and apparently I can bypass the IMA and keep the DC-DC converter just by unplugging the BCM and leaving the battery installed.


Will this still keep the 12V charged? It sounds like it should per research in Insight Central..

Also, will the CEL and IMA lights still be on with the bypass? I was still getting lean burn with the IMA/CEL lights on today. Lean burn is a non-negotiable must have. Having the IMA/CEL lights off is a bonus. If lean burn won't work with the bypass then I'll have to see if I can shut the lights off by spoofing something.

Ecky you said you lost lean burn with your bypass? How and why? Did you ever get it back?

Going to try the bypass tomorrow..

Unplugging the BCM works great. 12v will stay charged, though without the battery buffering it, charging will shut off for a few seconds if you rev over 4,000. I never found this to be an issue.

When you pull the battery out entirely you need to connect the high voltage leads that went to the battery directly to the pigtail coming from the DC-DC, so it can get voltage from the MDM to step down to 12v. Hit me up when you decide to do this, it's a pretty simple operation.

You'll have a CEL but no IMA light unless you add an Arduino to fool the ECU. Total cost can be less than $10 to make this, but you need to cut up the wire harness that went to the IMA system which makes it irreversible unless you have a spare. I might have a spare. Most cars won't lose lean burn, mine seems to be one of the rare cases. There are workarounds, but it ends up being a slightly more complicated procedure.

Hope this helps!

[mpg_numbers_guy]

Originally Posted by Ecky

This reflects my experience. 55mph is without a doubt worse than 50. I've found that I can get 100+ while cruising at lower speeds, but it seems like head-winds, hills, and things which interrupt steady-speed cruising affect the car more at lower speeds.

Those shifting points do not reflect my experience. I find shifting below 2250 delivers the best numbers, but our driving conditions may be different and you almost certainly have newer computers than are in my car. However I do find it easier to maintain throttle at 50 than at lower speeds

I can easily maintain at least 75 MPG cruising speed with lean burn in any conditions once the car is warmed up, with or without the battery, on both highway and non-highway driving. That's with the missing engine bay belly pan and still a little bit of drag on the wheels from the brakes (it's better but not gone yet).

Originally Posted by Ecky

Sounds like you had a catastrophic cell failure - one of them died in a way that could short out the pack, so it disconnected it entirely. Many packs die very gradually instead. Sorry to hear it happened.

Good fuel economy though, considering the conditions!

...

I doubt a grid charger would bring it back based on how it went. You could probably pull it apart and try to find the cell that died, but this isn't a long term solution - any replacement cell would likely get out of balance more easily and would need to be balanced regularly.

Even though the gauges weren't showing any assist or regen, I didn't notice any difference in acceleration, and the engine still started off the hybrid battery. It also didn't stall, indicating that the hybrid battery was still working somewhat. The only thing that didn't function was Autostop (guessing because of the CEL and IMA lights?). If all the signs are that the hybrid battery seems to be working at least somewhat, why isn't it showing assist and regen?

Do you still think that's what happened (the cell failure)? It didn't seem to noticeably affect the car's performance except for Autostop, yet none of the assist or regen gauges were ever lighting up. The battery went to one bar away from full and has stayed there ever since.

Originally Posted by Ecky

I think the car handles better without it personally, and you may not need Scott's rear springs since simply removing all that weight from the back will stiffen the rear up somewhat. You'll need to cut the rear springs a little if you want to keep the same ride height in the back. If you ever decide to go with a new pack or make the car a plug-in hybrid with a small lithium pack (150+++ mpg) I still have my uncut original springs which you're welcome to, and they're quite easy to put in.

How much would I need to cut them by? How much higher does the rear rise up with the battery removed?

Definitely would be interested in a relatively cheap lithium replacement whenever it becomes available. NiMH is a nighmare lol.

Originally Posted by Ecky

And yes, the car will still accurately track economy with a kill switch, it's only if you key-off to turn the engine off that you'll get inaccurate numbers.

Can it be wired up just like a kill switch on a "normal" car, or is there an Insight-specific method I need to follow?

Originally Posted by Ecky

Unplugging the BCM works great. 12v will stay charged, though without the battery buffering it, charging will shut off for a few seconds if you rev over 4,000. I never found this to be an issue.

Haven't revved it past 2600 yet. Is there a minimum RPM threshold limit too for charging the 12V? Or did unplugging the BCM remove that issue?

After bypassing the battery I drove into town to have my 12V tested. Bad battery as expected. Will consider a lithium replacement if I end up keeping the IMA bypassed. 6 miles into town and 6 miles back, with 4 stops, stalling it once, and taking almost a minute to exit the driveway (still learning how to drive a manual at slow speeds), and got 55.2 MPG on the cold engine. I did notice that the acceleration was slightly worse with the bypass compared to yesterday with the IMA light on...once again making me thing that the IMA isn't completely dead??

Originally Posted by Ecky

When you pull the battery out entirely you need to connect the high voltage leads that went to the battery directly to the pigtail coming from the DC-DC, so it can get voltage from the MDM to step down to 12v. Hit me up when you decide to do this, it's a pretty simple operation.

You'll have a CEL but no IMA light unless you add an Arduino to fool the ECU. Total cost can be less than $10 to make this, but you need to cut up the wire harness that went to the IMA system which makes it irreversible unless you have a spare. I might have a spare. Most cars won't lose lean burn, mine seems to be one of the rare cases. There are workarounds, but it ends up being a slightly more complicated procedure.

Hope this helps!

Will do. Thinking I might hook the IMA back up again and see how it does. If the battery is still assisting somehow without displaying it on the dash, does that mean it is regenning too without displaying it on the dash? What's the worst that can happen if the IMA just completely dies? Assuming I could just do the quick bypass and start it off the 12V then.

EDIT: Oh, another thing, I finally figured out how the grid charger works that came with the car. Plugged it in for a couple seconds and the voltage read 163V. Not sure if that indicates anything.

[Ecky]

That's odd with the battery, but it tells me that no, it's (probably) not a catastrophic failure after all. Mine never failed so I didn't get to see the full gamut of symptoms, but I understand that assist should go first, then auto-stop as it gets worse, followed by not being able to start with the IMA.

A very failing battery can cause a very small amount of constant background charging which can hurt mileage. Using a calpod (clutch) switch eliminates that, and can allow you to keep auto-stop and the ability to start with any but a completely hosed battery, as you won't be stressing it with assist and regen and the car won't figure out how weak it is. After a certain point 12v charging will shut off too, until you turn off the breaker in the back and unplug that computer. My guess is that a grid charging might bring it back for a few days or weeks, and you might get months or even a few years out of it so long as you prevent any assist/regen with a calpod switch. Up to you about what you do.

If you want to leave the option to go lithium on the table, you'll probably need to keep the pack, or at the very least the computers on it and maybe some of the sensors. I suppose you can probably get a cheap dead pack at a later date though should you choose to go down that path.

Charging at idle is affected without the IMA. I don't think the car will die if left idling in your driveway, but the DC-DC won't be able to get the battery up to 14v (fully charged) with the engine a 900rpm.

With the stock springs, probably between 1/4 and 1/2 of a coil to take it down an inch or inch and a half.. I'd measure ride height before taking anything out of the back, then cut a quarter of a coil, drive it around a bit then measure again and see how close you are. It's deceptively small, how little you need to remove to lower the car by an inch.

[Ecky]

It occurs to me that maybe your battery isn't actually dead though. Bad ground straps can cause the issues you're seeing, how are yours? I'm on my phone right now and can't easily dig through the thread to see if you've replaced those yet. I'd definitely look at those before tossing the system.

163v is what you ought to see for resting voltage with your battery, so long as it isn't fully charged or completely empty.

[Vman455]

I just had an idea (which I think I'll try on my car too):

Find one of the narrow coolant hoses running across the engine bay, if any (in the Prius, there's one that runs across the front of the car, from one of the overflow tanks to the radiator). Slit an oversized duct lengthwise, wrap around the coolant line, tape up. Easy air warmer. It will work best on trips long enough to get the coolant up to operating temperature, and won't be as effective as a dedicated intercooler because of the insulative properties of the rubber, but also not as complicated or expensive. And you could still route the end of the intake duct to the catalytic converter if you want.