How to get the infinite MPG without EOCing in a 2000 Caravan?

[Gealii]

Originally Posted by UltArc

I was under the impression DFCO still used fuel. And EOC doesn't engine brake the car while DFCO does.

if dfco does use fuel it is very minimal compared to normal

DFCO does not always engine brake so this is a touchy area.
Ex. my grand am dfco in drive does not engine brake

[101Volts]

Originally Posted by backpacker3

So you'll get out of your car pop the hood and pull the engine fuse then wait for the light to turn green put the fuse back close the hood get back in the car and then go. But you won't just turn the car off???????????

No, I wasn't very specific. I mean doing this at home just to see what happens.

Originally Posted by California98Civic

If you installed an injector kill switch, you could kill the engine without interrupting any other functions, like radio or fan. When you key back on, you'd get the usual momentary radio drop-out, but then all would return to normal. If you want to avoid multiple uses of the key switch, you could install a push button start alongside the key switch. That way the key could stay unchanged in the "run" position while you cut and restart the engine. But this is really all overkill in an automatic transmission car, because you can't cut the engine in an auto trans car while rolling (EOC, the big FE gains). And since you'd still be using the starter motor. So your best strategy, most cost effective and least expensive with no loss in fuel saving benefits is just to key off and on at lights longer than 10 or 15 seconds.

This works? I'm thinking of doing it at-home to see what happens. I tried pulling the fuel pump fuse and fuel pump relay but those aren't the injectors. My main goal here is to stop fuel from pumping in while keeping the van on, Otherwise (So ScanGauge II info is retained.) The gauge is due for an update in firmware though, At the 4.06 firmware it goes wonky if I shut the van off then turn it back on before the gauge has fully saved the info.

[2000mc]

to clarify, are you looking to turn off your fuel injectors when stopped, and not have to restart before driving off?

[101Volts]

Originally Posted by 2000mc

to clarify, are you looking to turn off your fuel injectors when stopped, and not have to restart before driving off?

That's the idea. Though now I'm thinking of doing it while coasting, too; It's beneficial at both times.

[2000mc]

when youre not moving, the energy to keep the engine spinning on your caravan must come from fuel delivered to the engine.
if youre coasting, the energy can either fome from fuel, or through the drivetrain causing engine braking

a couple years ago i tried to think through retrofitting an auto stop start feature, long story short, the options are A: to use an injector kill switch and restart w/key or use a starter button or B: buy a car that comes with auto stop start

[vskid3]

What you're doing is adding stop-start, but only doing anything on the stop side. Killing the injectors/fuel pump will stop the engine, turning them back on doesn't restart it if you're not moving/in gear, just like how your can doesn't start when you turn it to "run". You have to get the engine spinning again, either with the starter motor or the transmission if you're moving.

[Hersbird]

Killing the injectors while stopped kills the motor period, then it has to be restarted. Your van has this feature and as pointed out is done with the key. A hybrid does what you want automatically using only the brake and accelerator pedals. The hybrid can do this because it has a big battery and an electric motor capable of moving the car. So when you stop it killed or already had killed the gas motor, when you push the accelerator to go it starts moving the car with the electric motor and then restarts the gas motor but you hardly notice.
If its a problem with the scanguage powering down, wire it to a power supply that works with the key in the accessory posisition not just the run posisition, and don't turn the van key all the way to off just to accessory. Maybe your van is also diverting all power to the starter when you turn the key then I don't know.
I would not reccomend doing engine off coasting in that van. The power brakes will work fine for a little bit but then you will lose power assist and it will take much, much more effort to stop as well as losing power steering. Also you cannot restart it unless you come to a complete stop and put it in park.

[California98Civic]

Originally Posted by 101Volts

No, I wasn't very specific. I mean doing this at home just to see what happens.



This works? I'm thinking of doing it at-home to see what happens. I tried pulling the fuel pump fuse and fuel pump relay but those aren't the injectors. My main goal here is to stop fuel from pumping in while keeping the van on, Otherwise (So ScanGauge II info is retained.) The gauge is due for an update in firmware though, At the 4.06 firmware it goes wonky if I shut the van off then turn it back on before the gauge has fully saved the info.

In the build I used (adapted from others here at EM) I cut into the grounding wire for the fuel injectors. That will immediately shut down the engine, far better than the killing the fuel pump. A momentary switch for the injector kill and another for the start button, mounted right next to each other, maybe on the shifter itself. And there you go... DIY stop/start.

[freebeard]

I'm seeking a way to have the "9999 MPG" figure show up on the ScanGauge

At Permalink #6 we get the real question. First off, 9999 is not infinity. Does the Scanguage actually display the ∞ character?

What you are asking is: Is there any way to hack the Scanguage to provoke an error condition (possibly a buffer over-run) that will display erronious information. That should suggest some strategies.

My question is: Why?

[101Volts]

Originally Posted by vskid3

What you're doing is adding stop-start, but only doing anything on the stop side. Killing the injectors/fuel pump will stop the engine, turning them back on doesn't restart it if you're not moving/in gear, just like how your can doesn't start when you turn it to "run". You have to get the engine spinning again, either with the starter motor or the transmission if you're moving.

And a manual transmission would be of aid. Or is there a way to restart the engine with an automatic transmission?

Originally Posted by California98Civic

In the build I used (adapted from others here at EM) I cut into the grounding wire for the fuel injectors. That will immediately shut down the engine, far better than the killing the fuel pump. A momentary switch for the injector kill and another for the start button, mounted right next to each other, maybe on the shifter itself. And there you go... DIY stop/start.

That's useful, Thanks. I'm thinking of sending the Gauge in to update the firmware.

Originally Posted by Hersbird

Killing the injectors while stopped kills the motor period, then it has to be restarted. Your van has this feature and as pointed out is done with the key. A hybrid does what you want automatically using only the brake and accelerator pedals. The hybrid can do this because it has a big battery and an electric motor capable of moving the car. So when you stop it killed or already had killed the gas motor, when you push the accelerator to go it starts moving the car with the electric motor and then restarts the gas motor but you hardly notice.
If its a problem with the scanguage powering down, wire it to a power supply that works with the key in the accessory posisition not just the run posisition, and don't turn the van key all the way to off just to accessory. Maybe your van is also diverting all power to the starter when you turn the key then I don't know.
I would not reccomend doing engine off coasting in that van. The power brakes will work fine for a little bit but then you will lose power assist and it will take much, much more effort to stop as well as losing power steering. Also you cannot restart it unless you come to a complete stop and put it in park.

Thanks. Actually, I can re-start the engine in neutral with the van in "Accessory" mode. I've done it multiple times although it made a rather odd noise when I did it.

When I tried EOCing, I never did turn the key all the way off. I'd stick the van in Neutral and then switch to Accessory mode and back to Run fast (Which I later found shoots gas into the engine prior to starting it) and that would mess up the ScanGauge II readings in this particular Van/SGII Firmware combination. I also am able to maneuver the van without a power assist although it does require more muscle, And I'm sure I can stop the car without power brakes too as long as I press hard enough although I haven't done it much yet - In the driveway? Yes. On the road? That's an idea that has opportunity to come to fruition.

Originally Posted by freebeard

At Permalink #6 we get the real question. First off, 9999 is not infinity. Does the Scanguage actually display the ∞ character?

What you are asking is: Is there any way to hack the Scanguage to provoke an error condition (possibly a buffer over-run) that will display erronious information. That should suggest some strategies.

My question is: Why?

No, The "9999" figure is as close to the infinite symbol as that gauge gets. I'm asking how to get the van into a "No fuel is being put in" mode.

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