Hi, have filled up the Subaru on 97 Ron today (the first time I filled it up I put 95 ron in it but won't from now on).

My question is, will the car automatically adjust the knock parameters within the ECU or does the ECU need to be reset before it will adjust itself?

Thanks

 

The newage ECU has pretty good learning and should up the IAM

not sure about the classics?

Shaun

 

On a classic it is slower to adjust. IMO it will be quicker at learning if you do a reset. Reset the ECU then take it out for a 'spirited' drive and it should take advantage of the new fuel. Which super unleaded are you using? V-Power is the best and BP Ultimate the worst by far!

 

Cheers mate, how long will it take to recognise new fuel? Am running it on "supreme unleaded" Esso 97 Ron super unleaded. There aren't many other garages round me that have more than 97 Ron. One of them has that BP ultimate 102 though but won't use that!

The weird thing is, the owners manual says I can use either 95 Ron or higher, but when I open the petrol filler cap, there is a sticker that says use super unleaded

 

Fill the car up with whatever fuel your happy with ,disconnect the ecu for an hour or so then go for a drive (try to go on differnet speed limit roads 30mph to dual carraigeway/motorway speeds).

did this on my 93wrx when changing fuels and worked for me

 

Is the easiest way to reset the ECU by disconnecting the battery for an hour or so?

Have read the official way of resetting it by plugging in the plugs beneath the steering column, but the method looks a bit tricky

 

I tried to look for mine but couldnt find the bloody things and wasn't going to start unravelling all the tape that was under the dash so just disconnected the battery BUT if you have a standard alarm system on your car i don't know how that will be affected (if at all)
www.jollygreenmonster.co.uk on his help pages has the connector way of resetting the ecu.

 

Thanks, yeah have got the standard alarm system. Will attempt the proper (tricky) way of connecting the plugs etc just to be safe.

Is it unlikely the car would notice otherwise, if different fuel is in the car?

cheers

 

I would think the ecu would notice over time that the fuel is different but with resetting the ecu and going for a drive should sort it out in straight away.
Like i said this is from my experience of doing it on my car.

 

to reset newage ecu you need a tactrix cable and ecuflash software, the lead is available from the states about £60 delivered if you manage to avoid the duty, but would have thought the newage ecu would adjust far more quickly on its own

 

mine's a classic shape though (99) model so is probably the same resetting procedure for all Impreza classics? Although am guessing

 

Correct for more info check here Scoobypedia | Trusted knowledge for everything Subaru | Scoobypedia / Scoobypedia (under 'ECU')

 

If you plan on using the same fuel all the time dont worry about resetting the ECU, it will learn it over the course of about 3 tankfulls.

 

That sounds like good simple advice.

 

ok, thanks for the help. Will decide now whether to run on 97 Ron from now on or Shell Vpower - which I found out is round the corner from me too

 

BP ultimate is rubbish! I tried that and the car didnt like it at all. Went a bit better with a bottle of octane booster! I ran that out then filled with texaco super(its got some funny name that i cant remember) and is goes better on that alone than ultimate and a booster. I cannot for life of me find a shell garage near me!