2006 Honda Insight MT Build Thread
 

It's official! After months of searching I finally scored an Insight.

It's a 2006 manual transmission (with AC), red, with 254K miles on it. Car has been regularly maintained and runs well. In short, here is the good, the bad, and the planned ecomods:

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THE GOOD:

• Newer Bridgestone Potenza RE92s w/ only 7K miles on them
• The following were replaced 10K miles ago:
  • Exhaust
  • Drive belts
  • Stabilizer bar links
  • Engine mounts
• Transmission has NO grinding when upshifting or downshifting through any gear.
• Engine leaks NO oil
• No wet seatbelt issue
• No IMA light. IMA battery is not perfect but worked well. Working the battery hard over our 10 minute test drive depleted the battery down to 1/3 level in 6 minutes, and then it maintained that through forced regenning.
• Regular maintenance has been performed through the whole life of the car
• Comes with a cheap-ish looking grid charger. Haven't tested it yet to see if it works.
• Came with the original window sticker. Interesting to note, back in 2006 the car was first sold from the car dealership that my dad now works at.

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THE BAD:

• One wheel bearing needs replacing
• Engine valves possibly need adjusting
• EGR valve is suspected to be a little dirty (shouldn't be that hard to clean)
• Engine bay aero panel(s) are missing
• Paint is scuffed pretty bad
• Fender skirts are...bolted onto the car
• Left rear fender skirt is slightly bent due to minor accident 5 years ago.
• Front bumper is covered in chips.

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BUT, I was able to get a good deal the car. The car was well maintained mechanically and was a one-owner car until the person we bought the car from bought it. He only owned it for a week before selling it because they didn't like the car. So I bought it! On the drive home 54.7 MPG was obtained travelling mostly highway at 70 MPH, with only 32 PSI in the tires, no hypermiling, and forced regen the whole way.

During today's test drive we worked the battery hard over a period of 10 minutes, and depleted the battery down to 1/4 level in 6 minutes. By the time we returned to the seller's house, it had returned to 40% from forced regen. When we restarted the car to drive it home, the battery showed almost full, and then depleted down again upon accelerating on the highway, and then regenned to about 50% by the time we got home. Thoughts on this regarding battery health?

Planning on replacing the wheel bearing and getting the engine valves adjusted. Then I'll clean the EGR plate when I have time and either construct a coroplast engine belly pan or order the one off of IC....would coroplast sufficiently handle the heat of the engine? Will also be working with my dad to buff the car and touch up the scuffs in the paint. I'll probably remove the wheel skirts and see if I can't attach them using the regular clips instead of having them bolted on. I'll also probably scour a local junkyard to see if they have a red Insight I can score the front bumper cover off of.

Will also be getting winter tires mounted to the HX rims currently on my Civic for the Insight. Already have the Insight's RE92s inflated to 60 PSI. Planning the following ecomods during winter break from college (or as many of them as I can do in the 4 week timeframe):

• Scott's belly pan
• Daox's shift knob
• Regen switch
• FAS switch (using Natalya's setup)
• IMA disable/enable switch
• Full lower grille lbock
• Foam upper grille block (for winter)
• Warm air intake
• Rear wiper & motor delete, & hole plug
• Lean burn light indicator
• LED lighting
• Disconnect front parking lights wire
• Block heater
• Full belly pan
• Temperature spoof to get FAS at any temperature (Thoughts on this??)
• Cruise control (for longer trips)

And of course, a couple pictures:
https://ecomodder.com/forum/attachme...1&d=1542920214

Also got to have one next to the Civic it'll be replacing:
https://ecomodder.com/forum/attachme...1&d=1542920214

You'll notice that the foam grille block has been removed from the Civic. My mom is currently driving it since our van was totaled from a deer collision, and she is still looking for a Prius. We removed the grille block to avoid any chance of overheating due to inefficient driving. Tire pressure was also reduced on the Civic from 68 PSI to 35 PSI. Despite not too efficient driving style she has still been averaging about 39 MPG.

So excited to become an Insight owner! This is going to be a fun journey. I look forward to working on the car in my spare time when home from college. Not to mention the significantly reduced fuel costs even when compared to ol' Silver Aero.

Shoutout to Ecky for being such a great help and being very informative with all my questions on my "Dreaming..." thread!

I still need a name for my Insight!! Got any ideas?

Aw, HELL YEAH man! Got ya a G1 insight! Now, if I’m not mistaken, didn’t they remove lots of lean burn functionality in the later years?

I think I might be the youngest Gen 1 Insight owner out there. :D

Not sure about your question on the lean burn though. It seems to go into lean burn fine; but it's really finicky and really easy to get out of it. The lowest MPG in 5th gear with and without lean burn seems to correlate with what I've read.

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Took the Insight for a 9.1 mile drive today. I'm still learning how to drive manual so I didn't go on many main roads. Most of the roads were just rugged dirt roads with stop signs every half mile to mile. Anyway, I managed to pull 71.9 MPG over that 9.1 mile drive in the Insight! Considering I barely know how to drive the thing, and that it was all dirt roads, that isn't bad. My Civic would maybe have gotten 50 MPG on that drive, maybe. Only mod is 60 PSI in the tires. I do feel the harsher ride though! In my Civic I ran 68 PSI and didn't notice the ride being any harsher than 36 PSI, but 32 PSI to now 60 PSI in the RE92s sure make the ride rougher. I'll take it though for the MPGs.

Still trying to figure out lean burn though. Seems a lot more finicky than I expected. I don't feel anything when it goes into lean burn mode, but I can testify to about 70 MPG @ 35-40 MPH being the lowest fuel economy in lean burn, and about 45 MPG @ 38 MPH being the lowest fuel economy with the gas pedal floored in 5th gear. It's also really easy to go out of lean burn.

Autostop works at speeds under 10 MPH. I thought it was 20 MPH but I guess not.

Really loving this car!!

https://ecomodder.com/forum/attachme...1&d=1542996711

Here's what happened with the battery during drives with the Insight:

- Beginning of test drive when looking at the car for the first time: 100% battery
- 10 miles of city driving, little battery use: 1 bar down
- finished test drive since we didn't have a dealer plate at the time so we stuck to back roads
- Returned the next day to test more things and make an offer
- Test drove it again: battery, 100%
- Began driving. Went on more main roads and battery went down a couple bars. Then accelerated onto the highway and battery quickly drained to 60%
- By the time we finished the second test drive the battery was at 30% and had been force regenning for a while. This is partly because my dad drove it and uses clutch+brake to slow down instead of downshifting, and so gets no regen from braking.
- After buying the car dad started it to drive home. I followed in the Civic. He said battery again was full and went down to 60%. Was 40% by the time we got home after force regenning the whole way.
- Later that day I had my first manual driving lesson. He taught me to brake using clutch+brake as he knew. Because of the lesson, the battery went down to 20%.
- Drove it today over my 9.1 mile drive and got it recharged back up to 60% mostly from coasting in gear and downshifting when braking. Then suddenly towards the end of the drive after it had been at 60% for a minute or so it jumped to 100%. Then after using assist to accelerate from a stop, it quickly went back down to 60% and stayed there.

I'm guessing the battery has ~60% capacity left. Is this a reasonable conclusion to draw from how I described it's performance?

Decent economy for just starting out! You're actually beating my winter economy numbers already, but these cars are very sensitive to temperature and it's been wicked cold here - down to 6F yesterday. Driving from Vermont to Michigan I was averaging 55mpg at 55mph until I got out of the Adirondacks, at which point it improved to around 60mpg at 70mph, probably mostly due to increased outside air temperature. Right now I don't have my grille 100% blocked or my warm air intake installed (which I very highly recommend) since I expect to pull the engine in less than 2 weeks.

Probably worth mentioning but the IMA/regen switch doesn't work the same way on the (I believe) 05-06 models. I think you still get assist, just no regen, which isn't terribly helpful in my opinion. Might be useful with a falling battery but yours doesn't sound to be that. They do behave differently in other ways too than earlier years but I wouldn't call it better or worse.

Regarding batteries, what you saw was a "positive recalibration". It's probably an oversimplification to say that it has 60% of its original capacity, but that may not be far from the truth. The car was charging the battery until it saw the battery voltage begin to rise rapidly, suggesting it was full, at which point it adjusted it's capacity estimate and recalibrated the gauge. Even new batteries can have this happen.

Is it a front or rear wheel bearing? Rear you can very likely do yourself.

Only getting higher winter economy numbers because I have a hybrid battery probably. ;) Driven the same way you would easily beat me due to your familiarity with the vehicle. I'm just trying to drive it without stalling it right now. :D And wait, you're in Michigan right now??

Definitely planning on a WAI, but I don't have the time right now. I leave to return to college early tomorrow morning.

Wait really? Gr! Is this something that can be hacked/overridden? I couldn't find a "button" beneath the brake pedal like I think I remember you saying there was on, say, your 2000. Is it just a more complicated wiring thing or what? I seriously want a regen switch to help with charging the battery.

What other differences do the '05 and '06 have compared to the older models?

What about the fact that it discharges from full to 60% rapidly upon anything more than light assist?

I don't remember offhand except that it was on the driver's side. I think it might be the front one though. Planning on fixing it when I return for winter break 2nd week of December.

Yeah, my fuel economy numbers have improved every year, all else equal. In Detroit for the weekend, might see you at an Insight meet someday if you're into that sort of thing. ;)


I should clarify, the regen button still works. It's the clutch switch (also called calpod) which functions differently - depressing the clutch switch only prevents regen and not assist. A MIMA would work around this. There are actually a lot of more advanced IMA mods I never got into.

Off the top of my head:

-No oil/coolant heat exchanger in the 05-06. People have deleted these on earlier models and seen no consequences. Presumably with one you can get warmer oil faster and prevent it from overheating in very spirited driving, but it probably also adds a few pounds of weight.

-Three O2 sensors rather than two in 2001(?). Stricter emissions related. No effect on economy. I think the O2 sensors might have been different in every year of the car too. Careful if they ever need replacement.

-Sightly different computer programming every year for both main ECU and battery computers. Earlier cars had a few recalls for reprogramming to "improve" battery management and increase battery lifespan, but some speculate the had a small negative effect on economy. I know for certain very early cars could use 20-80% of the battery and it was later changes to 40-80% to greatly improve battery lifespan.

Even so, many computers are interchangeable.

-PCV valve is different on my 2000 than my friend's 2005, I expect the newer one is a better design.

-Aforementioned clutch switch behavior changes, unknown reason.

-In 2001 or 2002 they reduced the number of clips holding the exterior A-pillars on, presumably to make windshield replacement easier. It's common for shops to not reattach these trim pieces correctly especially in 2000 model years, and for them to blow off on the highway after a windshield replacement.

-Tan/beige interior rather than grey and black and the seats got sporty-looking holes in the head rests. I like the 00-04 interior colors better but ymmv.

-Rear speakers became standard in 2004(?)

-Different paint options for various years. I know the blue is much darker in later years. Citrus was no longer available. Silver and red might or might not be slightly different shades. I like the later silver better.

-Probably quit coming with a tape deck. :D

-In the 2000 model year A/C was optional and the CVT did not exist yet.

-OBD2 port moved from passenger footwell to underneath the steering wheel.

I know for certain my 2000 would not go into lean burn with the Arduino IMA bypass, while most others reported their cars did.



Hard to say. The battery gauge doesn't reflect what's really going on, nor do the assist and regen gauges. Sometimes you'll really have 1 bar of regen for miles but it won't show up. Full and empty on the battery gauge are generally ~40% and ~80% actual charge in the battery, but halfway down may or may not be 60%. I'd prefer if they were more honest, but presumably Honda had their reasons. Much like how fuel gauges aren't linear?

That's some interesting stuff Ecky!

I just did my middle/last o2 and was so worried it wouldn't work. I saw that Honda had them as a set and feared they were paired somehow. I bought two different ones at two different times but installed at the same time (still NTK, 24429 and 24430) and no problems over almost 500 miles now. Passed OBD2 inspection without issue. I paid $67 total after pricewatching on amazon vs over $300 from an online honda dealer.

And welcome to the Insight family! Not very many of us last year guys around.

I read the same things about some of the hacks people doing not working for us which is sad.

I bought a replacement rear O2 sensor because it was on sale on RockAuto for something like $8, even though my car didn't need it. I tried it out and got a CEL so it clearly wasn't the right one for my car.

I would definitely go to an Insight meet if it wasn't all the way in California or something, and was in the summer when I'm home from college. Do you know when the next one is?

Aaahhh, good. I'll need to look at the regen switch thread again. I saw one where wiring up the Rostra cruise control could make the "cancel" button act like a regen button, but it looked more complicated than the normal regen button I saw on here before.

Would the calpod still cause assist because of some weakness in the mod? since I wouldn't think the car would want to assist in neutral at all.

Three? Where is the third one? I only saw two when inspecting the engine.

I like the gray better too, but tan/beige hides dirt better. Then again, I didn't buy the Insight for interior design. :D I might focus on that after implementing all my planned ecomods.

Didn't get a chance to look at the speaker setup. Seems to be the same as the Civic, but sounds better because it's a smaller cabin.

Yup, CD slot instead.

How did you get lean burn then with your bypass?

Hm, true I guess. Is there a way to test the battery? How accurate is the fuel gauge? I would think it would be more accurate due to it being digital.

Thanks! Seems most people have 2000s. Do you know if the VIN # accurately indicates what # the Insight was in production?

I love these Gen I Insights, very rare over here (I think roughly 200 mademitmto the UK). Watching with great interest.

I'm not sure how accurate the vin # is for production.

Are you missing the cover for the tow hook in the front bumper? I was at a yard last week with one heavily chipped bumper, but it still had the cover. I have to drive back there to return some things anyway. I might be able to grab it for you.

They're fairly uncommon here too - I have actually only seen 1 or 2 other Gen 1 Insights in my life in the wild.

I'm at college now finishing the last couple weeks of this semester before I will be home doing any modifications to the Insight.

Yes, the front cover is missing the cover for the tow hook, and the paint is heavily chipped. Looks as speckled with white as a robin's egg is speckled with brown. Will be looking for a red replacement depending on what we can do as far as touching it up, but if I get a replacement I'd rather it not be as chipped up as this current one is.

Sticking this on here real quick:

I love how the average fuel economy of vehicles at home as increased over the years. Back in 2015 we had:

2015:
1999 GMC Sierra (both parents): 2500: 12-13 MPG
2004 Toyota Sienna (both parents): 25-27 MPG
2004 Honda Civic (me): 46 MPG (personal driving lmpg)
1993 Honda Nighthawk motorcycle (dad): 50 MPG
Approximate fuel used for all 3 to drive one mile: 0.080 + 0.038 + 0.022 + 0.020 = 0.16 gal = 25.0 average MPG.

December 2018:
Today my parents just purchased a Prius, so now our driveway:
2015-2017 dealer demo car (dad): ~35 MPG (31-38 depending on vehicle)
2008 Toyota Prius (mom): 49 MPG
2006 Honda Insight (me): 72 MPG (hopefully higher when I figure out how to drive it efficiently ;))
Approximate fuel used for all 3 to drive one mile: 0.029 + 0.020 + 0.014 = 0.063 gal = 47.6 average MPG.

I love how the most fuel inefficient car we have gets over 30 MPG. :D

I return home in 2 weeks. Time to finish learning how to drive manual + order stuff to mod that Insight! I'd love 100 MPG, but we'll see. ;)

Congrats! A first gen insight was my second choice, right behind the accord.

U WOT M8? That engine has screw type valve adjusters, which are really easy to work with and learn valve adjustments from. I made a thread on another forum instructing how to adjust the valves on a K24, you can check it out to see what you are getting yourself into. A valve adjustment would likely cost you around $300, so you could easily save that if you can do it yourself.

https://www.driveaccord.net/forums/1...ment-pics.html

Agreed, valve adjustment is very easy, can definitely do at home. You just need a set of feeler gauges, a #10(?) wrench, and a flat head screwdriver.

A certified Honda tech that my dad knows will be adjusting the valves. Seems too precise for me just to go at it with my fairly limited mechanical know-how. It'll be less than $200 and I should be able to watch him do it so I can learn how for any possible future valve adjustment.

What's the best winter tire to get for the Insight? Should I get all-season tires as winter tires, or get actual winter tires? What do y'all have experience with that works well but doesn't drop the MPG as much? Hoping to get a set mounted to my HX rims for the Insight after the semester finishes up.

Nokians are the best, and have excellent rolling resistance, possibly then better than the legendary RE92s. Definitely get real winter tires.

Are these it? https://www.discounttirezone.com/NOK...T_p_12979.html

What do you mean better rolling resistance? I thought RE92s provided the lowest rolling resistance and the best fuel economy....don't non-RE92s and especially winter tires add rolling resistance and reduce fuel economy?

The Nordman 7's are a great choice. They also have Hakkappellittas (sp?) but maybe not in the Insight's size.

There's nothing inherent in RE92s that necessarily make them the best, but they've been tested to be the best known all seasons in terms of rolling resistance, at least in the Insight's stock size. My technical tire knowledge is very limited, but I believe that one of the compounds used to keep rubber pliable (and therefore able to maintain grip) at low temperatures also reduces rolling resistance. The problem with using too much of this in all seasons or summer tires is that they'd wear our far too quickly as they're too soft when warm. It simply wouldn't be acceptable to have tires that last only 5-10,000 miles. Consequently you need to take your winter tires off when it starts getting warm (let's say above 40F with any regularity) or they'll very rapidly wear out.

This is worth watching:

https://youtu.be/GlYEMH10Z4s

Thanks for the info! Video made a lot of sense. Don't want to wreck my "new" Insight! Regarding tire pressure for winter tires, should I keep it at only 44 PSI sidewall max, or is 60 PSI still okay?

Max sidewall is 47psi in my Nokians. I run them around 48-50. My understanding is that higher pressure is often better than lower in winter depending on the conditions and to a point. Best to get additional opinions on this.

I ran Michelin Energy Savers at 60 PSI on my first Insight and loved them. They finally dry-rotted to the point that my son didn't feel comfortable driving on them and he swapped them out with new RE92's. It took him a while to break in the new ones and his mpg suffered from the new tires

The point being: don't expect great mpg for the first couple thousand miles on any new tire you choose

They are currently sold out pretty much everywhere that isn't charging an exorbitant amount for them, so I will have to wait for now.

Fall semester of college is over, and I'm back home for the next 4 weeks on break before the spring semester begins. This means...Insight time!

Reused the foam from the Civic's grille block to make an upper grille block for the Insight. This will be temporary until I build the lower grille block out of coroplast. Then I'll just use the upper grille block on extremely cold days.

And yes, I know I need to touch up that front bumper.

Got someone test driving the Civic this weekend. Hopefully it goes well and sells. Then I can go ahead and purchase what I need to modify the Insight (Daox's switch knob, Natalya's FAS setup, Scott's belly pan, etc.)

Quick question: does anyone have a link to a WAI setup for the Insight? I want to build one and have no idea where to begin yet.

https://ecomodder.com/forum/attachme...1&d=1544633648

I've found that RV and camper sized dryer ducting works nicely. I can't remember if it's 2 inches or 2.5, but it fits perfectly onto the air filter box. I routed mine counterclockwise in the bay to the catalyst but I've seen others who have left their air snorkel in place and gone clockwise (around the front of the engine).

Very noobish question, I suppose, but is the air intake what I have highlighted in the attached stock photo? And isn't a WAI just ducting routing from a hot area, such as the catalytic converter? How would I capture the heat from the cat through the ducting into the intake other than just pointing the ducting at the cat and hoping hot air goes in?

https://ecomodder.com/forum/attachme...2&d=1544639086

EDIT: Something like this?:

http://www.bugone.co.uk/Insight/Hotairmod.jpg

Just pointing it at the cat definitely works. The closer you get the ducting to it, the hotter the air you'll get.

The example you showed works very well. You can also take that whole black snorkel off, back to the air filter box, and run your ducting from there. The purpose of the snorkel has been discussed at length on Insight Central and it's not clear if it's just for noise reduction or if it slightly levels out the torque curve, but the car runs fine with or without it.

Oh, ok, so it really is that simple! Is it better to connect the ducting on the outside or inside of the intake opening? I'm guessing inside since the opening is 3" at it's widest point?

Edit: Although the one in the picture seems wider than 3 inches....

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

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.

https://i.imgur.com/wUnyqLp.jpg

Lower grille block & Warm air intake
 

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.

https://ecomodder.com/forum/attachme...1&d=1544734518

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 (:eek::eek:) 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.

https://ecomodder.com/forum/attachme...1&d=1544735665

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.

https://ecomodder.com/forum/attachme...1&d=1544735995

And the final product:

https://ecomodder.com/forum/attachme...1&d=1544736165

https://ecomodder.com/forum/attachme...1&d=1544736181

https://ecomodder.com/forum/attachme...1&d=1544736181

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.

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???

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..

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


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.

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.


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!

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).

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.

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.

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?

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??

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.

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.

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.

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.