Drive by Wire Throttle tune = ~3 MPG gain & more

[Cobb]

I believe hybrid revolt sells something like that for the older gen insight. The 2nd gen insight does this in eco mode.It numbs the throttle and cruse control so it is delayed, but further usage it does pick up its response.

[rmay635703]

I really need to find someone to tune up my cobalt this way, it has the same exact problem, 20% throttle gives you 95%+. A light touch and the rpms rev up to 2500 in neutral, impossible to rev match correctly due to the poor control.

[2007 ion2]

where are you in WI? I tap my throttle to rev match, and it works great. I also had trifecta remove the throttle lag, so fine control of the throttle is more predictable and actually seems at least more progressive.

[rmay635703]

Originally Posted by 2007 ion2

where are you in WI? I tap my throttle to rev match, and it works great. I also had trifecta remove the throttle lag, so fine control of the throttle is more predictable and actually seems at least more progressive.

I travel between Weston and Oshkosh most every week

[2007 ion2]

one thing I've noticed in general since the move from carburetors to fuel injection is the throttle pedal is more touchy.

[Miller88]

There are at least 4 different programs on my Focus. It's hard figuring out which one it will be using.

Originally Posted by 2007 ion2

one thing I've noticed in general since the move from carburetors to fuel injection is the throttle pedal is more touchy.

On some drive by wire systems (chrysler) it's horrible.

[Mr. Previa]

Interested thread. I don't seem to have that issue with my '13 RAV4. On a note, it does have the ECO/Sport buttons.

I also had a 2010 Prius. It was very smooth also. I even converted it to a plugin and it performed well in regards to the "surging" and pedal response. hmm, if memory serves me right the Prius also had the ECO/Sport buttons.

Perhaps manufactures, at least Toyota, are paying attention to this. IDK...

[ever_green]

Now that the throttle has been tuned to perfection, I have moved on to other things like tuning fuel and timing. I have already increased part throttle timing without issues and now have been looking at idle timing. I was wondering what effects ignition timing has at idle and coasting on fuel economy? I have read lower timing during fuel-cutoff/coasting means less engine breaking. If so this is a good thing for fuel economy purposes? My current timing is set at 15* at idle and up to 30* when coasting at speed. For some reason the manual (5-speed) ECU calls for only 9* of timing at low RPM idle. Why the difference?


Idle Ignition Timing Table

as for fuel I have not been able to induce lean burn. Lowering values above 0 simply just sends the car to open loop. However I have managed to replace it with leaner numbers. This is how the fuel map looks like:


closed loop fueling table. To calculate AFR subtract from 14.7. Ie. -0.1 means 14.6:1 AFR. I simply replaced all values at lower RPMs with 0 to run at 14.7.

[EdKiefer]

Originally Posted by ever_green

Now that the throttle has been tuned to perfection, I have moved on to other things like tuning fuel and timing. I have already increased part throttle timing without issues and now have been looking at idle timing. I was wondering what effects ignition timing has at idle and coasting on fuel economy? I have read lower timing during fuel-cutoff/coasting means less engine breaking. If so this is a good thing for fuel economy purposes? My current timing is set at 15* at idle and up to 30* when coasting at speed. For some reason the manual (5-speed) ECU calls for only 9* of timing at low RPM idle. Why the difference?


Idle Ignition Timing Table

as for fuel I have not been able to induce lean burn. Lowering values above 0 simply just sends the car to open loop. However I have managed to replace it with leaner numbers. This is how the fuel map looks like:


closed loop fueling table. To calculate AFR subtract from 14.7. Ie. -0.1 means 14.6:1 AFR. I simply replaced all values at lower RPMs with 0 to run at 14.7.

It been long time since i messed around with timing curves .
things to watch out for If my memory is still good . high timing in low rpm/load can increase emissions . whats in your chart doesn't seem to bad at low speeds (500-1500 ).
What was the stock values .
Manual model will have no load at idle vers auto is always in gear so can handle slightly more timing , I think the curves are mainly influenced by emission output then performance .

[brucey]

There was talk in another thread of having the throttle open when fuel injectors are cut off. Resulting in less pumping losses and able to ride DFCO longer. Would that be something that is programmable?