Speculation... resetting the ECU regularly

[mtbiker278]

I search through the site and didn't see much on resetting the ECU other than how to do it. My question is does anyone think resetting the ECU regularly, say on a quarterly basis, yeild any improvement on gas mileage? I know newer cars learn the way you drive and adjusts the A/F ratios, but would the factory setting be better for MPG than the ones the ECU learns over time?

[krousdb]

In my experience with the Prius, you do not want to reset the ECU. It makes sense to me that the default A/F ratios would be rich, not lean.

[Compaq888]

on my 99 obd2 car it helped. On the freeway when going up hills it stays in 4th, it just adds speed now. Before it would downshift to 3rd and waste gas.

[rh77]

If your Automatic transmission has Fuzzy Logic and learns your driving style (which you've perfected your style to get better mileage), it may take it's toll on efficiency until it's relearned. Otherwise, it would be interesting to know what it "remembers".

A definite downside is having to re-program radio presets, or find+input the security code on stock head units.

Now that I think about it my battery went completely dead when I first got my ScanGauge a couple of weeks ago when I was playing with it in the garage. The phone rang or something and I ended up leaving the ignition on all night, which had to have reset the ECU. I do now notice that it doesn't want to shift at 2500 rpm when I lift the throttle like it used to -- it wants to rev a bit higher. It'll get back to normal after a while.

Also, after every modification when tuning for power, it's recommended that the ECU is reset. Maybe the same holds for efficiency mods...

RH77

[krousdb]

Originally Posted by rh77

Also, after every modification when tuning for power, it's recommended that the ECU is reset. Maybe the same holds for efficiency mods...

RH77

I would think that the opposite would be true.

The tour del sol is coming up in May. Here is a link for Prius drivers with advice for the Tour De Sol. The very first thing that it mentions is that you should not disconnect the ECU.

http://techno-fandom.org/~hobbit/cars/prius-rally-hints.txt

If the Tour De Sol was scheduled for june, july or August, I would probably go for the $10k grand prize for achieving over 100 MPG in a completely stock car. But mid May in New York will likely be too cool to achieve 100 MPG. You will need at least 70F, but maybe the weather will cooperate and someone will win the prize. Good luck to them.

Link to tour de sol..
http://www.nesea.org/transportation/tour/2006Monte_Carlo_Rally.php

[mtbiker278]

So would you guys say that it would be a good idea to reset if you've been driving hard/have some hiccups with the engine/trans, and otherwise just leave the thing alone if you've been driving efficiently? (run on sentence I know)

Also, would it be a good idea to figure out a way to keep the ECU powered when you diconnect the battery for some other work. How would you go about doing that?

[SVOboy]

I guess to keep it powered you could just tap into the ecu power somewhere and leave it powered. I rarely undo my battery to work on my car though, so I've never thought about it. I do reset my ecu like twice a day though,