I have read something about the MINI having an "adaptive" Engine Control Unit (ECU). My understanding is extremely limited, but I have the impression that somehow, the ECU adapts itself to the owner's driving style, giving better performance or better gas mileage, sharper or smoother throttle response, etc., depending on how the car is driven.

I've also read something about this taking place over a 500 mile interval. And I've read that it's a good idea to reset the ECU whenever mods are installed, so the ECU will start fresh with the new mods.

Is this basically right so far?

I've got a lot of questions, some of them because I would like to be able to get the "most" out of my car. (For instance, I'd like to get good gas mileage around town, but I'd also like to be able to get maximum performance when I go do a track day.) Some of my questions are also just curiosity. Here are some of the questions I have:

Is this "500 mile" interval just the first 500 miles after the reset, or is the ECU continuing to adapt? IE, is it the first 500 miles or the most recent 500 miles? Put another way, if one installed some mods and didn't reset the ECU, would the ECU gradually adapt to the mods or not?

What exactly is "adapting" - A/F ratio? Ignition timing? Drive-by-wire throttle response to changes in gas pedal position? Other stuff?

What happens when you reset the ECU? Does it go to some sort of "generic" setting midway between performance and economy? In other words, if you reset the ECU and then drive hard for 500 miles, can you actually get more performance than you would get from a freshly reset ECU?

Do these adaptions affect the car at WOT (wide open throttle) or only in-between throttle settings? In other words, will a car that's been driven like a granny come out like a dog on the dyno? Will a car that's been driven hard all the time come out as an extra-strong car on the dyno? (And where will a car with a freshly-reset ECU come out? Between the granny car and the hard car?)

How much of a difference do the adaptations really make? Kumho Kid (on MINI2) says he's dyno'ed over 200 cars and seen variations as large as 135 to 160 whp on stock cars from the same model year. Could ECU adaptations account for some of this? If so, does anyone have any idea how much?

Andy (in the current "200hp possible" thread) says Helix has seen a much smaller variation, in the range of +/-5hp. Could Helix be resetting ECUs before testing the cars?

If someone wanted to get the most accurate picture of the effects of engine mods, should you: (1) reset the ECU, (2) dyno the unmodified car, (3) install the mods, (4) reset the ECU a second time, (5) dyno the modified car. It seems to me that that way, you'd be eliminating any effects caused by the "adaptive-ness" of the ECU (adapting to the driver OR the equipment installed on the car), starting with a "fresh" ECU for each dyno run.

Can anyone point me to an authoritative article on how the ECU adapts, and what effects this has on the car?

Thanks!

 

The only thing I have really heard BMW/MINI refer to as adaptive is the steptronic transmission software - i.e regarding the MCSa:

"This new automatic transmission also features AGS (Adaptive Transmission
Control). AGS allows the transmission to adapt in accordance with the
driver's driving style. For example, the transmission will build the revs
for longer before changing gear if it 'knows' the driver enjoys driving to
the car's limits. "

So, aside from the ECU working with varying AF ratios and emissions/fuel issue I'm not sure what else it really adapts to. I have not heard of drive by wire adapting natively (beyind the above on autos) which is why aftermarket software can make such a difference with that - I had Dinan software improve that and have heard others say the Shark, etc changes the DBW responsiveness.

 

The MCS has the ability to "learn" the following adaptation parameters:

Misfire Adaptation
Knock Spark Adaptation
ECT Throttle Adaptation
Lambda Adaptation
Knock Control Adaptation
MAP Adaptation
Dynamic Trim Adaptation
Idle Speed Adaptation

See this page for an explanation of how one type of adaptation works:

http://www.ross-tech.com/vag-com/cars/fuel-trim.html

Anyway, I have dynoed my car and others both immediately after doing mods as well as several hundred miles afterwards. I have also dynoed cars without clearing adaptation values and dynoed cars with clearing adaptation values. I haven't seen any significant changes in power output due to the presence or absence of adaptation values. See this thread:

https://www.northamericanmotoring.co...ad.php?t=56219

Cliff notes:

If you perform a mod that makes more power, it will make more power on the dyno ... instantly. If you change back to stock, it will make less power ... instantly. Examples can be found in dynos of exhausts, intakes, chips, piggybacks, etc.

 

This is an easier post to respond to than the first one. Slight variation in process. The ECU controls the function of the transmission in the MCSa. So, if you immediately back off the engine revs after you reach 65 MPH, the ECU will "adapt" and automatically back off the revs when you are merging onto the highway after you reach 65 MPH.

You can temporarily reverse the adapted program (in the example, the backing off of the engine revs), but that entails punching the go pedal before the ECU would ordinarily back off the revs.

I doubt if it really takes 500 miles for the adaptation to "learn" - it was more like 50 miles with my MCSa. You can reset adaptation by pulling fuses (similar to if not the same as restarting your PC) and forcing the ECU to return to default (factory) programs. Then upon reconnecting the fuses, the ECU will go into an adaptation mode to re-learn the driving style. Unfortunately, I don't know which fuses are pulled to reset the ECU in the MINI.

I really doubt that adaptation is responsible for different hp and ft/lbs measurements. The difference is more likely explained by variations in dynomometer, physical conditions when the test was run, and sample-to-sample variations of the engines in each car.