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Discussion Starter #1
I have been thinking about this for sometime now, and I kept reading the posts on the "Coasting" thread, seems that most people here are concerned about the forced autostop, they seem to think that the engine will not restart once you are on a forced stop, this is true if you turn the ignition key off and then back on again, this is not really a forced autostop, in my view forced autostop would have to keep all the safeguards Honda designed on the Insight.

After following a lot of the wiring schematics on the service manual, and making some notes I decided to try it, I installed it today, took the car for a drive, and it works really good.

When you are on a forced autostop, and you loose vacuum on the brakes, the engine will start by itself, it works.

If you release the clutch, the engine should restart, it works.

If you suddenly release the brake pedal, it starts, so it works.

The power steering works, since it's electric, it works even with the engine off when you exceed 7 mph.

There are two things required for FAS, one is to eliminate the spark, the other is to "turn off" the fuel injectors.

The spark can be taken care of by bypassing the fuse #7 on the fuse box, inside of the car, this is the fuse that controls the coils.

I have only gone this far, because I wanted to see if it really worked, now I know it does, hopefully I will be doing the injectors kill tomorrow or early next week, but in the meantime I mounted a switch so I can kill the engine at will.

I drove in a shopping center today, and as soon as I got in the engine still kept running, so I just pushed the switch, and it turned off.

Now, I would not recommend turning the engine off at high speed, but I feel that if we are going to try to get the most mileage we should have as many tools to do it with, and this is one more for me. :D
 

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Discussion Starter #2
After reading my last post I just want to let every one know that by bypassing the fuse, I didn't mean to remove it, just relocate it, the fuse is still in place, just in a different location, those who are handy with wiring know what I'm talking about.

Before I hear any comments, I just did it to see if it would work, it does.
 

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Sharp eyes there Calipod :!: :)

AFAIK when the ECM (Engine computer) fails to "see" the spark then injectors will also be shut down.

**But this needs to be verified BEFORE continuing with this mod.**

"Forcing" this type of auto stop _without_ shutting down the injectors can have some _very_ bad side effects due to fuel building up throughout the system. Also it would appear that the BCM will not have its low SoC or thermal limits management available in the decision. So its likely that a restart under these conditions will _require_ a key on crank of the back-up starter. Hmmm... could be VERY bad depending on the situation.

I'd also _highly_ recomend for those that will add this mod that a "dead man" switch be used (one that takes continuous pressing to maintain. In electrical terms a momentary contact type switch) thus simply removing your finger from the button will return the car to normal operation.

*** IMPORTANT***
DON"T mess with yellow wire loom air bag wires :!: :!: :!: else they _may_ deploy. Serious injury or *death* can occur if your hit at the wrong angle.

HTH! :)
 

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Another possibility might be to interrupt the speed sensor, to make the computer think that the car has stopped. You would have a pushbutton that interrupts this signal so the car goes into autostop, and then when you release it, suddenly the car would notice that it's actually going 30 mph (or whatever). Would this bring it out of autostop or can you coast up to any speed without having it restart? I keep forgetting to try this.
 

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Congratulationd Calpod
Heed John's warnings.
A neat way to add a switch to an automotive fused circuit is to sacrifice two fuses. The first sacrificed fuse needs to be blown out, and I know I dont need to tell anyone how to do that.
The blown fuse is sanded so that the top of the tabs rear metal is exposed.
The blown fuse is placed in a vise, which acts as a heatsink, and a holder.The two exposed metal tabs should be tinned with solder until they are thoroughly wetted out.
The second sacrificed fuse has one of the legs sanded so that it sits on top of the blown fuse bared top. They are soldered together, with a fast touch of a hot soldering iorn, as the good fuse could be damaged if it gets too hot.
A wet rag on the good fuse can help here.
The final step is to take the two wires from your switch (which should be rated for at least the amperage that the fuse was), and solder one to the good fuse the other to the second leg of the blown fuse.
This basically makes a plug in switched fuse, that can be simply removed and replaced to put the circuit back to stock. The neat thing about this is that several of them could go to the same multipole switch so that more than one could be switched with a single flip, yet they all remain protected and stock.
What I also do to finish off the adapter, is to cover the exposed metal with hot melt, to form an easy to grab insulated handle.
Here is a photo of how it looks plugged into the fuse panel.
http://pages.cthome.net/genesisone/SwitchedFuse.jpg
 

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Discussion Starter #6
I used and "Add a circuit" adapter they sell at the autoparts, it allows you to have another circuit, but at the same time it allows you to do all your work outside the vehicle, when you're done, just plug it in like a regular fuse and you're set.

I did not have a blown fuse, so what I did is cut up a good one, removed the tabs, then soldered the wire from the new fuse holder, from there it went to the momentary switch, after the switch went back to the fuse holder.

I'm still working on the fuel injector cutoff, all 3 injectors end up at a common wire, this is where I will install new wires going to the switch.

I just have the coil switch for now, I tried it this morning on a street where there was no traffic, at about 25 mph, I saw the light far ahead turn yellow, so I pumped the brakes, they worked fine, at the fourth time, the engine turned back on by itself.

I know this is annoying when you come to a stop and sometimes the engine still keeps on running, now I can shut it down anytime I want to, then just put the car in gear and it will start without having to use the key, I love it. :D
 

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Calpod said:
I just have the coil switch for now, I tried it this morning on a street where there was no traffic, at about 25 mph, I saw the light far ahead turn yellow, so I pumped the brakes, they worked fine, at the fourth time, the engine turned back on by itself.
HUH :!: :?

With the coils(s) off how _can_ the ICE self restart :!: :?: :?: :?
 

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Discussion Starter #9
I have a momentary switch, I just press and release it, I have not tried any faster, but I'll try tomorrow morning on my drive to work.
 

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A cleaner approach would be to temporarly override the VSS (vehicle speed sensor) input to the ECM with a fixed frequency generator with the same Hz the the VSS generates at, say, 10MPH. So you hit a button and the ECM suddenly thinks you are going 10MPH and will do normal autostop if all the other conditions are right. Heck, you might even try grounding it (i.e. 0MPH), this can be done with just a simple switch.

If the ECM does any kind of sanity checking on the VSS signal, it may generate a CEL.
 

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Discussion Starter #12
flunkysama wrote:
A cleaner approach would be to temporarly override the VSS (vehicle speed sensor) input to the ECM with a fixed frequency generator with the same Hz the the VSS generates at, say, 10MPH. So you hit a button and the ECM suddenly thinks you are going 10MPH and will do normal autostop if all the other conditions are right.
The problem with the VSS is that if you go this route, the minute you release the button it will "see" the speed you are going and it will re-start the engine.

I tried today the Forced Autostop, at speeds above 60 MPH, it will try to restart the engine, thanks to MIMA I can see on the display the electric motor pulsating on and off trying to restart the engine, I don't care much about turning the engine off at that speed anyhow.

At speeds of less than 40 I can shut it down, no side effects, only the lights turn on sometimes, like when you turn the ignition key off and back on, but it restarts by itself.
 

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When the engine stops using the switch at > 20MPH, does the green AS light still flash?
FYI
The VSS is a 0-5V square wave , that has a frequency of about 100HZ at 90 MPH, and of course stops on either 5V or 0V when the car stops. The signal goes to The following places, ECM,MCM,EPS,Guage assembly, and Climate control. Not sure what the effect would be if only the ECM lost it?
 

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Discussion Starter #14
Thanks for the info. Mike,

I've only seen the green light flash on time, another time some of the other lights came on, including the oil light, but since the engine if off, it's OK, the engine starts when I put it in gear, I was able to force Autostop even in first gear, the car will never go in Autostop when you're in first gear.

I don't think I'll go the VSS route, I don't think it will work.

flunkysama, would you like to try it and see if it work?

I will try to set up the fuel injector "Kill switch" tomorrow.
 

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Calpod
I think John is probably correct about the fuel injectors being stopped when the spark stops, otherwise you would be feeding gas into the cylinders, and would get one hell of an explosion and probably blow up the cats and exhaust, and shoot 2 foot flames out the tailpipe, once you got it started again. :shock:
Since that has not happened, the injectors are probably being turned off by the cars emission control system.
Better be careful, I would hate to read in the paper that one of the MIMA equipped Insights went up in a ball of flames, and that the driver was killed, trying to save a little gas. :wink:
 

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As fuel delivery to the cylinders cuts off when rpm's are over idle and the foot is off the gas pedal, one could presume that, if you were to do the forced engine stop in this order:
1. lift your foot off the gas
2. press the ignition interrupt button
3. press the clutch and put the transmission into N

then there would for sure be no unburned fuel in the cylinders. Otherwise, there would be a couple of revolutions worth of fuel in there before the engine stopped, and let's discuss the possible harm from that. (Damage to the O2 sensor? Catalytic converter? Clogging the plugs? - just being careful...)

Thanks for pioneering this... I think I'll be installing it sometimes this week too.
 

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Discussion Starter #17
Anytime your foot is off the gas pedal the fuel injectors cut off, remember the "Fuel cut mode".

It will turn the fuel injectors back on at 1000 rpm to keep the engine from stalling, I've done my homework on this one, spent several hours going thru the service manual.

I'm still going to install the fuel injector cut off switch just for added peace of mind sometime this week.

for those interested in this mod, read the service manual, it shows you the wiring diagram, go to page 11-18, 11-45, 11-91, also for the coils look at page 4-14, 4-17.
 

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Yes, I guess my logic had one big hole right in the middle :D . Sorry about that...
(The fuel injectors will come back on as the engine is spinning down regardless if there is a spark present, right?)

By the way, if I can ask - where did you get the service manual? Is it available for download someplace? I don't assume it is free, right?

Let us know where are you cutting off the fuel injectors and how, please...

Thanks!
 

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the manuals are on ebay all the time. thats where i got mine.
 

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Calpod said:
Anytime your foot is off the gas pedal the fuel injectors cut off, remember the "Fuel cut mode".

It will turn the fuel injectors back on at 1000 rpm to keep the engine from stalling, I've done my homework on this one, spent several hours going thru the service manual.
IMHO, I think the fuel cutoff works when vacuum level is greater than idle vacuum level, ie. the MAP sensor determines when you're decelerating. The same fuel cutoff idea has been employed in carbureted engines for years. my 86 dodge (mitsubishi) colt had this feature.
 
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