ECU Relearn - real or not?

[mrapoc]

So does the following procedure actually work or do anything?

 

1. Disconnect battery for 30 mins
2. Reconnect
3. Start engine but do not touch anything
4. Leave to idle for 30 mins
5. The car will relearn fuelling etc. and after 30 mins will drive with better mpg etc

My local skoda guy says it news to him

My tuner says its "internet talk"

 

I'm all for more mpg, but surely it relearns as you drive and I don't fancy losing 30mins of idle fuel

[sepulchrave]

The idling part is nonsense, reset the ECU and drive normally for the best results.

[devonutopia]

The ECU does learn, but it learns from your driving style - so I can be pootling up the M5 @ 70 and then come off and then want/need to accelerate hard, but the car won't be the same.

Drive the car hard, and it will give more.

[mrapoc]

So I could reset the ECU (take battery off 30 mins) and then drive hard. This would produce 

 

Better response 

or 

Better MPG

 

or both?

 

I'm happy with the power, but its much harder to get mpg "easily" when compared to my golf which is practically the same engine only heavier (and 100k more miles)

 

or just ignore it all and thrash it once a week as a minimum, other than that just drive it how I want

Edited 18 February, 2014 by mrapoc

[Kgod1991]

Doesn't matter how I drive mine I get the same I go from one extreme to the other dependent on mood... And music.

On subject though, I've heard of resetting the ECU after you've added mods that could affect performance so that it takes it on board straight away. But id say the 30minute idle thing is nonsense if you've disconnected the battery just drive it normal for abit then go back to how you would

[faboka vrs]

We talking diesel or petrol?

[Bazmcc]

Basically, nonsense.

 

The ECU adapts to and adjusts fuel timing and air flow readings within about 10 seconds based on what comes back from the temp, pressure, and timing sensors.  Then it'll regulate as normal based on those sensors after that.

 

Placebo is an amazing thing, especially combined with what the americans refer to as a 'butt dyno'.

[rwbaldwin]

To fully erase learned values use adaptation channel 00.

If you want to do a terminal-30 (power disconnection) reset, you will also need to short the battery terminal clamps together (AFTER HAVING DISCONNECTED THE BATTERY) which ensures all modules have any capacitors in them discharge.

Both procedures can be useful if you have corrected multiple sensor problems or if modules (including the ECU) have become 'confused'.

[vrsRob]

The ECU does learn, but it learns from your driving style - so I can be pootling up the M5 @ 70 and then come off and then want/need to accelerate hard, but the car won't be the same.

Drive the car hard, and it will give more.

 

Funny you say that...I drove from Kent to Yorkshire at the weekend, drove fairly normally there but wanted to get back in good time so was a little more enthusiastic on the return journey and now she feels a lot more lively and responsive!! 

 

I have given up on the "drive for amazing economy" thought, if I wanted that, I would but a Greenline - however, when I drive carefully, if I really try, I can still get over 70mpg! 

 

BUT I have a vRS so I have decided I should drive for the enjoyment of it!! That way, good fuel economy is just a by product!! (I still get over 50mpg when it is driven enthusiastically!!)

[AaronMountford1990]

So basically..rag your car and your MPG increases? I like it ..very R&R

[@Lee]

The ECU does learn, but it learns from your driving style - so I can be pootling up the M5 @ 70 and then come off and then want/need to accelerate hard, but the car won't be the same.

Drive the car hard, and it will give more.

My dyno figures agree :sun:

[devonutopia]

After every track day I do, my cruise home afterwards always gives me better mpg.  I have no idea why really.  After a day at Cadwell Park my 300 mile drive home said I did approaching 70mpg....

[@Lee]

After every track day I do, my cruise home afterwards always gives me better mpg.  I have no idea why really.  After a day at Cadwell Park my 300 mile drive home said I did approaching 70mpg....

damn my lack of sixth gear :(

[mrapoc]

Well at the moment I am set to get 500 miles to the tank, trip computer has hit 50mpg once. 45mpg if I drive like a VRS. 50mpg at a stretch if I drive like a boring fart. 

 

Tried 6th gear, 5th gear, 50mph, 60mph, 70mph, 80mph, motorway, a roads all seem to sub 50mpg unless I'm really lucky. 

 

Will try adaption 00 and also the battery trick. No idea how you guys get 70mpg

[Getulus]

Well at the moment I am set to get 500 miles to the tank, trip computer has hit 50mpg once. 45mpg if I drive like a VRS. 50mpg at a stretch if I drive like a boring fart. 

 

Tried 6th gear, 5th gear, 50mph, 60mph, 70mph, 80mph, motorway, a roads all seem to sub 50mpg unless I'm really lucky. 

 

Will try adaption 00 and also the battery trick. No idea how you guys get 70mpg

Me too mate,best i've ever seen was 53mpg at 60mph on a flat stretch of motorway,mines a BLT which apparently can be quite inaccurate but i'd love to see 70 mpg lol.

[LewisVRS]

I don't take much notice of MPG really, just see how many miles to a tank I get each week. Works for me

[AaronMountford1990]

managed 62.8 on a run, hard to keep there tho!

[felicia16v]

No better after the remap then?

have you checked the dash is reading it correctly?, the biggest difference between the golf and the fabia is the tyre size and possibly the overall gearing, not as much weight difference as you may think.

[AaronMountford1990]

that was after a reboot, pas died so took battery off for ten minutes then drove off (once connected again haha) and managed that..tank showed 250 miles when doing 30 around town then 395 when I hit motorways

[mrapoc]

No better after the remap then?

have you checked the dash is reading it correctly?, the biggest difference between the golf and the fabia is the tyre size and possibly the overall gearing, not as much weight difference as you may think.

 

It does seem better after a remap, better distributed power and easier to hold there. I think I could get big MPG if I could hold it at a speed easier but it seems to just need that extra bit of throttle to keep it there. i.e at 60mph it can read like 70 odd mpg, but it quickly starts to drop in speed. Might be worth me checking brakes for drag but it does seem to roll nicely in neutral. 

 

I'll leave it till I get through this tank and then have a looky what mileage I get out of it as everyone says the mpg calculator may be lying! big time! I found a big difference by letting the air out of the tank - obviously nothing to do with mpg, but i did feel a bit sad when I only got 400 to a tank last time!

[jamwatn]

The people who think it doesn't work haven't tried it!

[faboka vrs]

With a diesel you need to ask yourself, what does the ecu need to learn? And how can it do it?

With a petrol it's easy. Most cars under normal driving run around lambda 1. It's uses the 02 sensors to measure the lambda. If required it uses the short term and long term fuel trims on top of the normal part throttle fuel map to achieve this. Resetting the ecu clears these trims back to 0.

Edited 20 February, 2014 by faboka vrs