cster

So now I guess I'll have to drive around under 3000 rpm until it runs out.
I stuck in some NOS octane booster from Halfords to be safe?
Probably get about 400 miles to the tank

corradoboy

It'll be reet With a shot of NOS just drive it as usual.

uzzy-swr

is it harmful to the engine if you put in normal unleaded or is it the same. i've been filling up with unleaded on some occasions.

corradoboy

It's recommended to use 98RON fuel in PPP'd or other modified cars otherwise it could run lean. Standard UK cars are fine on regular 95RON, but once the performance creeps up, or particularly JDM cars which are set up to run on 100RON fuel unless remap'd, you should use 'super' or whatever at 98+. The OP stated he topped it up with some NOS so should be OK.

IRC450STI

Drive normal & dont thrash it or do high speeds and it will be fine

tath

it's not running lean that causes the knock, it's the petrol's inherent lesser ability to resist spontaneous ignition.

I think you're worrying needlessly, chuck some booster in and forget about it.

cster

OK - I think I'll drive it as though I have the family in the car - only half mad!

bluenose172

iTrader: (2)

It'll pull ignition slightly if it detects knock(due to lower RON), thing is it then has to 're-learn' after you've put the decent stuff back in. Don't know much about the Octane Booster you've used, but you'll be lucky if it's added 1RON.

s70rjw

iTrader: (2)

It will run fine. The PPP cert. fully explains the consequences..ie a slight loss in power, nohting more.

cster

Yeah,you are right. I spent £10 then got home and checked it on internet.

jasonius

iTrader: (1)

It will pull some ignition when on boost (NOZ is cr@p BTW) but will be safe. You will probably/should notice this as a loss in urge/responsiveness. Drive it as normal and run the tank as low as you dare (20miles beyond orange light.. ).

Then refill with your normal fuel (pref. V-power..) drive home and disconnect the battery for 30 mins or so. Reconnect battery and drive steadily until you can hold 3000rpm in 2nd gear for 20 seconds or so. Hey presto, the IAM should be back up to it's max and off you go..

If you don't do a reset it'll take at least two tank fulls for the ECU to advance back to it's optimal setting..

Lol, you'll probably find that you'll get LESS mpg from the 95ron than 98+..!

FWIW all newage impreza's (Std UK inc) recommend you use min 98ron. Take a look inside the filler cap..

fpan

iTrader: (11)

My 2007 WRX (bought from Germany) states to use 95 RON, I doubt UK ones are different!

jasonius

iTrader: (1)

Then I stand corrected..

I wonder if the 2.5's (MY 06>) are all the same..?

Certainly ALL 03-05 (blobeye) state 98ron, even my EU 05..

Any 2.5 hawkeye owners know what the recommended fuel is printed inside filler flap..?

D1CCY

Look on the bright side - at least you didn't fill it with Diesel.

cster

97 on the STI I think.

cster

Well - I drove around on part throttle and kept it under 3500 revs and got..... 26mpg!
Moral of the story - RAG IT!

jasonius

iTrader: (1)

Lol, have you noticed any/much difference in performance..?

Monky

Will be fine just fill it up with super next time and get on with it

cster

I did notice that under 3500 rpm, it wasn't very quick.
Once the V power was in - no wuckin furries!