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ECU Reset Question?
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Old 23 Jun 2004, 07:20 PM   #1 (permalink)
Young Scooby
 
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ECU Reset Question?

How frequently can I reset the ECU as it does make quite a difference? Can I do it as often as I want :? :?:

Also what is the best way to reset the ECU :? I heard you can do it by pressing the brake and disconnecting one of the battery terminals or by plugging and unplugging the green and black switches under the dash then driving it slow and then hard once they're unplugged again :?:

Just had to add I've done it twice using the green/black plug method :?
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Old 23 Jun 2004, 07:32 PM   #2 (permalink)
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Daz - well you can reset the ECU as often as you like but doing it too often would not be a good idea. The reason I say this is that once you have reset the ECU's parameters everything is wiped. The ECU now relearns knock correction amongst many other things Now if the ECU retards your ignition timing say for example because the car is running slightly lean or something then the ECU will make the necessary adjustments to allow for this......the car will generally feel slightly lethargic etc to cater for the knock correction and thus maintain engine safety. However if you reset the ECU too often then the car may well not being allowed to sort out its SAFE parameters before you reset them all again (hope this makes sense ?) If you are in this scenario then the car has a problem which needs to be sorted (a remap for example) not continuous Resets. Another thing to bear in mind is the early Impreza ECU takes a long time to reset its parameters if for example the ignition has been retarded having had a dodgy batch of fuel. The later ECU's 1998 onwards I believe relearn a lot quicker and can literally restore full power (after such an ignition retard) after a tank of good fuel....with the older ECU's it takes mulitple tanks to get it back to what it should be, this is another good time to reset the ECU

I hope this helps ?
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Old 23 Jun 2004, 07:34 PM   #3 (permalink)
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You can reset the ecu as often as you like.
Nelson wrote, about doing it after the car being filled with poor quality fuel, after any mods being done etc.
On my 02 and new 03 could not see the black plugs on either, so had to do the neg terminal off trick, (confirmed by garage) followed by the drive at 2500 revs for 6 secs and seemed to work.
All i can add is if its worked for you then that would be the sensible way to go in future.

buzz
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Old 23 Jun 2004, 07:47 PM   #4 (permalink)
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Thanx Guys

I have a MY99 and I only put in Shell optimax or BP Ultimate97, cost a fortune but is like viagra for my scoob 8)

Would you say its safe for me to reset it once a week :?
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Old 23 Jun 2004, 10:06 PM   #5 (permalink)
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Daz - as per Buzzs comments - its also a good idea to reset the ECU after carrying out a Modification

Once a week IMHO is a bit to regular. Maybe once every few months etc or sooner if you suspect a bad batch of fuel. My previous comments still apply though - if you need to reset the ECU that often, because the car is down on power then I would suggest that your car has a problem and resets are not gonna help you find it, unfortunately Please also remember that the if you plug the 2 black ECU connectors together then and turn on the ignition then you can see if there are any historic fault codes
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Old 24 Jun 2004, 11:13 PM   #6 (permalink)
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resets work well on the pre 01 setup

but not on the 01-newer

the ECU's differ and dont 'forget' much
you really need the correct program / data logger/ select monitor to clear the car properly...especially if you get a bad code. The new ECU will not 'just forget" and the code / check engine light will come back on.... (trust me, been there done that... still dealing with it! )


on the older GC body.. reset by disconnecting neg terminal (10-20mins should do)
reconnect
start the car but do not touch the gas pedal
let it idle for a bit

and there ya go....

Jamie
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Old 25 Jun 2004, 06:08 AM   #7 (permalink)
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Subaie Gal, are you running a stock ecu on Bernsie the rally wagon? or do you have a remapped one?...
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Old 25 Jun 2004, 08:14 PM   #8 (permalink)
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Thanx Guys

There were no error codes it flashed frequently and kept regular but just seems like it feels a bit fresher with a reset! Probably my imagination

Will do it once a month or so then!

Thanks again for the information nice to know some guys are clued up
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Old 25 Jun 2004, 08:48 PM   #9 (permalink)
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Quote:
Originally Posted by 1999Turbo
Subaie Gal, are you running a stock ecu on Bernsie the rally wagon? or do you have a remapped one?...
investigating remapping options with EcuTek as remapping should be legal for 2005 rally rules... currently in my class (production) remapping isnt exactlylegal... but nor is it exactly illegal

so i've got a 2nd ecu and we're going to try to get it sorted in time for 2005

should see good torque improvements!

Jamie
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Old 25 Jun 2004, 08:49 PM   #10 (permalink)
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Great So it is possible to have a swop ecu? (or spare one) Like one for certain conditions?
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Old 25 Jun 2004, 10:45 PM   #11 (permalink)
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Quote:
Originally Posted by 1999Turbo
Great So it is possible to have a swop ecu? (or spare one) Like one for certain conditions?
yeah sure but the beauty of EcuTek is that you have 2 map settings...

1 - normal - street driving

and 1 - aggressive/race mode

and you can toggle in between the 2!
EcuTek is the STUFF!!!

http://www.ecutek.com/


Jamie
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