Adjusting accelerator travel required for motor activation?

[KarenRei]

In default Insight operation, there's no assist in the first 1/2 to 2/3rds or so of accelerator travel, and then assist kicks in after that. Is there a (not obscenely complicated) way to have a button that changes how much accelerator travel you need before assist kicks in (aka, without changing how much the accelerator affects the gas engine)? I want to get one of those multi-rate grid chargers when they become available, and it'd be nice to be able to have a mode I can put the vehicle into where it'll use assist much more readily.

Oh, and I don't have MIMA.

[MN Driver]

No way to adjust it, you can turn it off with a clutch switch (also known as CARD/Calpod Assist Regen Disable) but if you want to control assist, MIMA is the only way to do it.

Sounds like you might have the old battery programming mine pushes assist with less than half throttle, about 85% engine load(by scangauge) and it slips in assist and by 90% engine load its got a pretty heavy load of assist going. With a low engine speed that is happening under 1/3 throttle for me quite often if I'm not using a clutch switch.

[KarenRei]

Dang. I've already got a clutch switch, plug-and-play MIMAs are listed as unavailable, and I don't feel up to building one from scratch. :P

I was looking at my driving habits and realized that with a grid charger, I'd be able to get a not-irrelevant amount of my driving energy from electricity even on the stock pack. I do random long cross-country trips and a ~50 mile round trip twice a month, but most of my daily driving is short hops -- 12 miles between home and work (can charge at both), 2 miles round-trip to the grocery store, 1.5 miles round trip to the nearest mall, a couple miles to friends' houses, etc. But there's not much point to grid charging (apart from the occasional cell balancing) if I have to be gunning the gas engine to force it to use assist and take advantage of that 10kW. The best I'd be able to do is to run in too high of a gear for the gas engine as much as I could, so long as the RPM stayed high enough.

[02insight]

I think you are talking about adjusting the TPS signal? In that case, I remember someone did a mod that adjusts that and allows some control of the IMA assist. But it also adjusts the fuel delivery since that is controlled with the TPS as well.

Here is the thread:
IMA TPS Mod, less assist, now works

[KarenRei]

I find that thread a bit hard to follow. What all does the TP signal affect? The goal is to only change when assist comes on, not anything else. You say it affects fuel delivery as well?

[02insight]

the TPS signal tells the ECU how much the throttle is open when you step on the gas pedal.

although assist might not be controlled only from the TPS, because you can have the same throttle position in 1st or 2nd gear, but assist will kick in more in 2nd gear, because the IMA probably also looks at the MAP sensor to determine engine load.

but when you mess the the MAP or TPS signals, you are also messing with the fuel mixture, so most people dont mess with them, and just get MIMA.

Here is another mod for the TPS sensor, where its signal is made smooth.
Autospeed - TPS MOD

[BillR]

Here's an option that may give you what you need without resorting to modifying anything. While it's correct that you need to use a fair bit of throttle to convince the computer to engage the electric motor, once it is engaged you can back off the throttle quite a bit before the computer disengages it. I use this technique when accellerating.

Move off from a stop in first gear - Shift into second gear - apply enough throttle to engage the minimum electric assist (a quick jab to about 1/2 throttle will give you about 5 bars) - back off the throttle to the minimum point that will sustain electric assist (you have to find this point with a sensitive foot) - allow the electric motor to do as much of the work pulling the car up to speed as possible - when the electric assist drops out as the speed levels off in second gear, shift to third gear and repeat, then fourth, then fifth if you need to get up to higher speeds.

I know that this isn't exactly what you're looking for, but it's the best way I've found to use the most electrons and least gas for short trips.

HTH,
Bill

[Eli]

Originally Posted by BillR

Here's an option that may give you what you need without resorting to modifying anything. While it's correct that you need to use a fair bit of throttle to convince the computer to engage the electric motor, once it is engaged you can back off the throttle quite a bit before the computer disengages it. I use this technique when accellerating.

Move off from a stop in first gear - Shift into second gear - apply enough throttle to engage the minimum electric assist (a quick jab to about 1/2 throttle will give you about 5 bars) - back off the throttle to the minimum point that will sustain electric assist (you have to find this point with a sensitive foot) - allow the electric motor to do as much of the work pulling the car up to speed as possible - when the electric assist drops out as the speed levels off in second gear, shift to third gear and repeat, then fourth, then fifth if you need to get up to higher speeds.

I know that this isn't exactly what you're looking for, but it's the best way I've found to use the most electrons and least gas for short trips.

HTH,
Bill

This works well and I used to do this before MIMA. If you're very careful with your throttle modulation, you can get assist with the FCD at 55MPG. But that's about as good as it gets.

I believe the stock system uses MAP data, not TPS data to determine whether assist is needed.

[Willie Williford]

Bottom line is that ASSIST IS DETERMINED BY THE "LOAD" on the engine.

HTH
Willie

[joecvt]

Originally Posted by Willie Williford

Bottom line is that ASSIST IS DETERMINED BY THE "LOAD" on the engine.

I agree that the MAP sensor is primarily used for determining assist level but I think the VSS and TPS is also used....The ECM determines driver's intent and looks at current speed and load.....And at times, how cold or hot the battery is....

While I was messing around with the Low Speed Auto Stop mod, I was faking the VSS to the ECM and at speeds to about 10-15MPH, I could make the ECM send assist signals to the IMA to provide assist with just barely touching the throttle (so not much MAP sensor stuff going on).

Once it gets beyond a certain speed, MAP probably IS the most deciding factor when temps are within the norm (I did uppercase for Willy )

For those that say....if I modify the MAP sensor to send a different voltage to the ECM to introduce assist "sooner"..., while that portion of the mod may work, it may also screw up driveability....

JoeCVT = Just your average CVT owner