Project: Zombie Insight (2000 Honda)

[Funny]

Originally Posted by RobertSmalls

Speaking of engine kill switches, I want to tone down my idle air control valve. If a cold engine can idle smoothly at 1000RPM, why does the Insight idle at 1800RPM when it's bitterly cold? When the engine is above 100°F, it idles smoothly without an IACV, and when it's above 150°F, it doesn't need to idle at all.

I think that it idles at that speed initially to force oil to the top of the engine. The colder the oil the higher the viscosity and, subsequently, the more difficult to pump. I believe that it goes to 1000RPM after a short time right? How long? Maybe you could just mod the ecu signal to shorten the high idle to a more suitable time? Or eliminate the high idle entirely and modify the oil delivery to the top of the engine, maybe a Prius-like coolant thermos with oil in it instead? Hmmm, that gives me a good idea....

Good Luck!

[RobertSmalls]

Originally Posted by discovery

Realy cool idea with the relay, i like it very much. Does the auto stop work when you are seatting at a red light? I guess it does, by turning the switch off. So cool, good job. Also what is MIMA_L stand for?

Auto-stop works when you touch the brake pedal, which turns the switch off, provided that the heater is off or at ECON, the tranny is in Neutral, the ambient temperature sensor is above ~30°F, the vehicle is below 17mph, etc. So, no, not often.

MIMA_L stands for Manual Integrated Motor Assist (Lightweight), I think. It's vastly simpler and less expensive than the feature-rich MIMA, which you can buy for $1000.

Funny, the oil pump does okay at 1000RPM. AFAIK, the only reason for high idle is emissions. The cat has to light off in a certain amount of time, even when it's very cold out. Well, I care more about petroleum consumption and CO2 than NOx. I'll keep air out of the engine bay, wrap the cat in aluminium foil and maybe fiberglass, and it'll light off when it lights off. I'm not going to pour fuel on it to speed up the process.

[user removed]

My 37 Ford would get 60 PSI oil pressure cranking the starter at 100 RPM (about 1/3 of the cranking speed of a modern car) after 5 seconds.

Ignition off, cold engine, 74 year old technology, no oil filter, ancient parts.

You start a modern engine and you have oil pressure faster than you can say "yes". Modern oil filters have check valves that keep them full of oil.

The only problem I see with lowering the fast idle speed Robert, would be you also need to reduce the enrichment or you might get your plugs loaded up with raw fuel.

Not sure if the Insight controls fast idle speed and mixture in a coordinated way.

I just drive it away quickly and use the fast idle to propel the car through my neighborhood at 25 MPH. In your case (with a manual) you have the choice of using a higher gear to keep RPM lower and extract more work out of the fast idle-cold enrichment time period.

That is what I do with my VX, keep the RPM low in the first few tenths of a mile, which also helps with cold engine fuel consumption.

regards
Mech

[bikeracer]

Dearest RobertSmalls,

I have very little experience choosing components and designing circuits, switches, etc. Could you recommend specific parts for the mods you're posting (or post the parts you used if those would be your recommendation after you've put it through its paces)? I am itching to build and implement them. RadioShack is nearby, and I'm at least aware of the Jameco electronics catalog.

Many thanks

Originally Posted by RobertSmalls

Yep, electrical modifications can be fruitful, especially in a hybrid. I finally got the IMA inhibit switch working almost exactly the way I wanted.

In stock form, the car is too eager to use electric assist. I found it used assist almost every time I left a red light. Drawing energy out of the battery, then putting it back in with the gas engine, is generally less efficient that just using the gas engine alone. When I'm ecodriving, I want to use only as much assist as I can pay back with regenerative braking (and I brake as little as possible).

The solution is an IMA inhibit switch. When the ECU thinks you've got your foot on the clutch, it won't use assist or regen. The simplest IMA inhibit switch is just a toggle switch that, when closed, electrically connects the two wires going to the clutch pedal switch.

That works fine, but you have to switch it off manually for regenerative braking. This is a distraction, and it results in missed regen opportunities. I added a relay so that when the brake lights are on, the IMA inhibit switch is ignored.



I installed this mod in the driver's footwell, using inline splices to tap into the brake lights and the clutch switch at the pedals.


When I get around to constructing MIMA_L, I might move all my electrical mods to a breadboard near the passenger footwell. Between MIMA_L, the engine kill switch, IMA inhibit, and IACV inhibit, I'll need to cut 8 wires and tap into 7 others. This is best done right where the wires enter the ECU.

[RobertSmalls]

Bikeracer,

As you know, I'm glad to have another mod-inclined Insight owner on the forum. There aren't many of us. I also hope Ben gets his IRX on the road soon. Hopefully, you'll develop good mods that I can learn from.

I used "18-22 gauge inline splices" and "female flat blade connectors", both from DigiKey. The switch, I actually stole off my bicycle, and it fits in the blanks to the left of the steering wheel, below the power window switch. I used a relay out of Ford Taurus. Relays have a little circuit diagram molded into their side, which looks like the one I drew. You need a five-pin relay. You could get all the parts at an auto parts store, RadioShack, or online.

To clarify the drawing, the ECU delivers +5V to the clutch switch on the red wire. Splice into that, and run a wire over to the correct pin of the relay. Likewise, run a wire from the green/yellow wire from the brake pedal switch to the coil of the relay. The electrical resistance of the relay circuit needs to be "much larger" than that of your brake light bulbs. >50 Ohm is fine. If your relay has less, add a ~500 Ohm resistor.


Once I've built and tested my MIMA_L + FAS + IMA Inhibit board, I'll post a parts list and some pictures.

[bikeracer]

Many thanks. I think the mods you can expect from me will be aerodynamic in nature. I've got some connections at the MIT wind tunnel, so it's possible that the car might get some tunnel time once I've got things taped to it.

[bikeracer]

You mentioned having built a kill switch. How'd that work?

What sort of bicycle do you have that has/had a relay on it?

Originally Posted by RobertSmalls

Thanks, MetroMPG.Just this and the engine kill switch for now. I really want to re-do the engine kill switch on a circuit board using Mike Dabrowski's schematic, which allows the DC-DC converter to run, and restarts the car when you shift from neutral.

Speaking of engine kill switches, I want to tone down my idle air control valve. If a cold engine can idle smoothly at 1000RPM, why does the Insight idle at 1800RPM when it's bitterly cold? When the engine is above 100°F, it idles smoothly without an IACV, and when it's above 150°F, it doesn't need to idle at all.

Maybe if I wire a resistor inline with the IACV, I'll get a lower idle. I'll see if I can figure that one out some time.

50.1 mpg through a little snow on the way to work yesterday. Initial temperature: 8°F. Regenerative braking: barely regenerating due to the frigidity of the battery.

74.4mpg on 20 miles of gently rolling country roads today. 80% throttle up steeper hills, DWL + lean burn the rest of the way, 50mph typical. Winter tires, dry roads. It makes me wonder what kind of FE I'll get in the summer.

[RobertSmalls]

Originally Posted by bikeracer

You mentioned having built a kill switch. How'd that work?

Badly. The dash lights up like a christmas tree, and the engine tries to re-start if you're going fast enough and your foot isn't on the clutch. I have parts in the mail for a better system.

Or maybe the answer you were looking for is: Splice in a 3PDT relay where the fuel injector wires leave the ECU.

Originally Posted by bikeracer

What sort of bicycle do you have that has/had a relay on it?

2008 Iron Horse Triumph with DIY 12V illumination system. The bike was cheap, and it's good enough that I can keep up with my cycling club, even with the rack for my saddlebags, my 5lb lead-acid battery, 3W LED headlight, and obscenely bright LED trailer taillight.

[bikeracer]

what a rig. that bike sounds like fun. Next step, suspension.

do you have any suggested readings for beginning electronics building/modifications? something that covers, for example, telling whether the relay I ended up buying is normally closed or open...

[user removed]

That should be normally open.

regards
mech