ECU Reset - well worth it

[Nelson]

At the weekend I carried out an ECU reset on the Scoob and am very pleased with the way the car has settled down.......it certainly feels like full power has been restored. if you have had any problems, bad fuel etc - then it can be a good idea to reset your ECU. This is not a difficult thing to do but after carrying out the procedure will restore original factory settings. Over the next 100 miles the ECU re-learns the parameters which often leads to a better running car. However if you have a sensor that is failing and or failed then again the reset is a good way to find out about it.

If any of you want anymore information on this just let me know

[newie]

Karl
Tell me more .....

[Nelson]

Ok - if you climb into the drivers side footwell (best to slide in on your back so you are looking up toward the windscreen) you should find at the base of the steering column 2 sets of plugs. 2 Green and 2 Black....they may well be taped up out the way so look closely. Firstly connect the Black Plugs together and then turn on ignition but don't start car. What you should see is an ECU light flashing without interruption.......this means that the car has no fault codes stored and you can move onto the next step. If however at this time the ECU flashes irregularly then you have one or more historic fault codes stored in the memory. Study the ECU flashes and what you are looking for are different length flashes. The ECU logs codes as follows - short flashes are units of 1 - longer flashes are units of 10.....so for example if you say one long flash(10) - then another long flash(10) and then a short flash (1) then you have error code 21. You may have more than one code logged and the codes are seperated by longish pauses. I have a list of all the codes and what they mean if required.

Anyway if you have any codes stored then write them down and switch off ignition. Now conect the 2 green plugs leaving the black ones also connected. Again turn on ignition but don't turn car over. You may need to switch off your immobiliser at this point too as this will allow your fuel pump to engage . What you will now hear is your radiator fan start up and slow down, and various other clicks from the engine (these being sensors). Now slowly depress throttle to the floor, hold for 3 seconds and then release. Now start your engine and leaving plugs connected go for a drive, if possible do not let your engine speed drop below 10mph. Do not use boost and only drive with light throttle. You should find that after a short while the ECU lamp flashes regularly - YOUR ECU HAS BEEN RESET ! Disconnect all the plugs fromone another but If it does not flash then this would indicate that you have a problem and you should reconnect the black plugs to see what the problem is ?

Once ECU has been reset I suggest taking your car for a spirited drive. This will allow your ECU to relearn the parameters. I have carried out this procedure a number of times for myself and others and have always had favourable results

If you are unclear on anything I have said then just say and I'll explain further

[newie]

right i'll give that a go.......its just the flashing bit that might confuse me so i'll just see what happens and if i have any probs i'll give you a shout

[Big E]

that sound like a good idea might do that this weekend

[Pakin]

I reset the ECU by disconnecting the neg terminal and then hold down the brake pedal for around 30 second. I'm guessing it should work the same way, everything is different, drive the bloody heck out of it, etc.

-paK +1

[skylight]

Karl, - thanks very much for the detailed post.

Originally Posted by Pakin

drive the bloody heck out of it, etc.

Thats the best part about all of this

[Westside WRX]

FYI...a tidbit from Shiv at Vishnu tuning:

Re-Mapped ECU Learning Trick 10-20hp in 5 seconds

Originally posted by Vishnu Performance
Just a little trick that has been shown to accelerate the factory ECU's ignition timing learning process.

Background: There is something called "Ignition Advance Multiplier". It represents, by some complicated algorithm, the average learned positive knock correction applied to the ignition maps. It's represented in 1/8th degrees increments. 1 being the lowest and 16 being the highest (1/8 to 2 degrees in absolute terms).

The "happier" (knock free) the car is, the higher the number will be. Conversely, the lower it is, the more knock prone it is. This number, after ECU reset ore ECU swap defaults to 8 and usually creeps up to 16 (if well mapped) through normal driving. Depending on driving characteristics, this can happen within a few hours or a few weeks. Well, here's a way to make it happen in about 5 seconds ....

First: With the car fully warmed up, reset the ECU. This can be done by killing power the ECU or by simply pulling off the neg. battery terminal and pressing the brake pedal for a couple of seconds.

Second: Drive to a nice open road without traffic. Don't go on boost until you get there. Put the car into gear (3rd gear works the best) bring the revs up to 2600rpm. Push the go pedal down slightly so boost stays right around 2-4psi. You will need to MAINTAIN 2500rpm and 2-5psi for approx 5 seconds. You can do this by left-foot braking gently as to prevent acceleration. During these few seconds, the advance multiplier (which you can't see so you'll have to trust me) will go from 8, to 12 and then to 16. Works like a charm. And on our reflashed ECU, is worth an immediate 10-20 horsepower

In an attempt to save a lot of dyno time between reflashes (when the advance multiplier resets itself), I do this little trick after every reflash. In a typical dyno session, it's not unusual to reflash the same car up to 5 times. On the dyno, all I need to do is tell the dyno to hold revs to 2600rpm. Then I just lay on the throttle until I see a few psi of boost... Bingo!

Warning: This little trick artificially speeds up the learning process. This is only a good thing if the re-mapped ECU is mapped properly. If there are trouble-spots where knock is present, this trick will make it even more present. So be careful!

Cheers,
shiv
www.vishnutuning.com

[skylight]

Thats an interesting article... Thanks for taking the time to pull that out of the box. Looks as we will all be attempting a ECU touch up soon!

Gareth

[Nelson]

Can't comment on the disconnect neg terminal and hold down brake pedal ?? The process I follow takes a few minutes I know others disconnect the battery overnight and it does the same job.....thing that worries me there is the alarm.

All I can say is for the first day or so the car felt o.k - however having completed 100 miles or so of mixed driving the car feels as Tiger Tony would say GREEEEATTTTTTTTTT
the added bonus with doing this is you will soon find out if any of your sensors have or are failing.

I have the full list of ECU codes if required and please let me know how you get on with the reset if you should do it.

P.S Its also a good idea to make sure the car is up to normal running temperature before resetting the ECU.

[Anonymous]

hi guys, just fitted my induction kit and thought i'd have a go at the ecu reset. Looked under the dash but could only see green plugs and sockets.
Did the neg off and hold brake on bit.
Took scooby for a drive, did the hold at 2500rpm bit for a while the gave it the spirited bit!
Now, i've done what you all said, but, call me dim if you like, where will i find these ecu lights i've read about?

It did seem to go some after all that i must say, nice sucking noise too (gonna connect a long tube through the bulk head me thinks!)

So how do i know if the ecu has been done??

buzz

[Nelson]

Buzz - you would only see the flashing lights mate if you had done the rest as per my post. By doing the Battery Beg etc you have (I assume) reset it another way....basically the plugs I mentioned at the bottom of your steering column would need to be plugged in for you to see the ECU check light that I talked about.

As far as I know and please note that I have never used the battery neg off to do a reset, your ECU should be reset. Over the next 50-100 miles it will relearn its parameters....don't worry if the car doesn't feel as quick to start with cos it has to relearn the values, you should find however it gets better.

As ofr the PLugs you found the Green ones by the sounds of things and the Black ones which look very similar will be there but they are no doubt taped out the way....you could do with a torch really

Anyway see how you get on.

[buzz]

thanks for that Nelson, but where do I veiw the ecu lamp? is it on the dash?

Did go Bloody well after though!, took the wench out for a spin and bravely let her have a go and she said there was a noticable difference!

cheers

buzz

[billythekid]

I just looked for these connectors on my 03 WRX and could not see them??

[newie]

Had my ECU reset done by Neil (aka N_collins)

and i must say what a difference it has made

car is sooooo smooth now and the turbo kick-in is so much smoother too.

well pleased .......good shout Nelson 8)