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Here on this board and in the owners manual it says to use 91 octane gas. HOWEVER, when picking up my new 03 WRX yesterday, the salesman explicitly stated to use 87 octane gas... saying more is just a waste of money!

Is this true? My mechanic buddy, who was with me, thought that MAYBE it's because Canada has more stringent regulations regarding the quality of gas related to the US... and so 87 octane is fine in Canada, but across the border, 91 would be the minimum.

Has anyone else heard of using 87?

I will call other dealers in the Vancouver area and see what they say. I will report back here sometime... my internet's down at home right now due to Kazaa crapware (I think).
 

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No, you need to use 91 oct. all the time. The salesman was part right but mostly wrong. Using anything higher than the oct. specified is a waste of money, however if the car demands 91 oct. it is because the ECU and timing is programmed for 91 oct. and using '87 will cause the ECU to "de-tune" itself and run on low power to prevent damage, however, if the ECU cannot compensate enough for the lower oct. gas, then pre-ignition (knock) will start to occur which can kill an engine in as little as a few seconds.

It has nothing to do with the gas regulation any country, it has to do with what type of fuel the car's ECU is programmed for.

Also, Turbo cars are more suseptable to engine 'knock' than non-turbo cars because of the nature of forced induction, there-fore it is even more imperitive to use the recommended octane. It can also be beneficial to use a HIGHER octane than recomended on a turbo car because the computer can 'learn' the other way and make MORE power with higher octane, while a non-turbo car for the most part will not (which is why it is a waste in most cars).

Hope this helps...

-Jason
 

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You probably ought to have another 'learned' dealer contact the dealer who told you that and inform him of his harmful advice.

A stock WRX is pushing some pretty mighty heat out of the turbo into the throttle body and down into the cylinders. You are probably already experiencing some pre-detonation.

Higher octane = higher threshold to fuel igniting too early due to the high exhaust temps. Bottom line, higher octane has a higher flashpoint meaning it won't ignite as quickly to a certain temp as will a lower octane.

The recommendation in the owners manual is good advice.
 

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You could just show the 'salesman' the tag inside the fuel filler door that says USE PREMIUM FUEL ONLY

Salesmen usually don't know squat... My father sells Dodges.... it's funny when I know more about the crap he sells than he does. I think he's still a little bitter that I bought a WRX Wagon and not the GT Cruiser. ;)
 

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Use what the manual says.
You shouldn't have any problem with 87 because the ECU will retard the timing to prevent knocking.
But you're not going to get full power.
 

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Dealers are so, so, SO dumb.
 

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94

Living in Canada I have run mine on 87 once. ( by mistake! . there was this hot chick at the pumps and........well....I wasent thinking) lol anyway after about 10 km I noticed the difference!! YUP!! is was that bad...Ms.ECU retarded everything. felt like my 323 lmao. run the Sunoco 94! she loves it ! ( in the car that is);)
 

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lol
having sex lol
i use 93 also all the time
it's only a dollar or $2 difference between 87 and 93
this is for the sake of ur own
:)
 

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around here it goes 85 87 93. I definately use the 93 EVERY time, and my wife knows to do this also. There is a gas station in a nearby town with like 95-97 that my friend told me about, but I can't find it. It is definately worth wasting the $$ on IMO!!
 

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your dealer is an idiot and he doesn't know what the manual says. 03 manual says 91 minimum. most boosted cars say the same thing.

now using anything other than what the manual recommends (in the case of a manual which recommends 87) is indeed a waste of money, though some cars (many fords in particular) have terrible fuel injection systems and either require you to use 91 every so often to keep their knock under control, or use of a fuel injection cleaner / octane boost every now and then when filling up.

is 91 octane any cleaner than 87? does it have more detergents? absolutely not. that is a myth.

i use 92, which is the highest sold in our area. people who have 93 or 94 have pollution problems. those who have 91/92 have less pollution. it's all controlled by the government, your available octane at the pump.
 

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all good responses guys. in short, stick to premium. we get 94 at sunoco here in boston, and 93 at all the other places.


Hot_Dog said:
Do you think it matters where you get your gas (Chevron, Texaco, etc...)?
no difference. only recently i've started to be choosy about brand. not because of quality of gas, but b/c i don't want to fund oil companies based in terrorist sponsoring countries. i only buy gas now at a handful of the major brands (as much as possible anyway) so that i KNOW my money isn't being filtered down to the people funding the operations of our enemies.

stick to the brand names.

dR
 

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Need help! Darn dealers!

I have a new 06 wrx sedan. I got it October 27 this year and I have about 1025 miles on it. I have been running 87 in it because the dealers said it was ok. Should I change immediately to 91 next time. What happens to my engine when it is on the cheap stuff. Is it because of the turbo / ecu linking up?

Sorry, Noob with a hopefully not screwed up car.
 

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I have a new 06 wrx sedan. I got it October 27 this year and I have about 1025 miles on it. I have been running 87 in it because the dealers said it was ok. Should I change immediately to 91 next time. What happens to my engine when it is on the cheap stuff. Is it because of the turbo / ecu linking up?

Sorry, Noob with a hopefully not screwed up car.
Dont listen to dealers. All they want is your wallet.
 

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I have a new 06 wrx sedan. I got it October 27 this year and I have about 1025 miles on it. I have been running 87 in it because the dealers said it was ok. Should I change immediately to 91 next time. What happens to my engine when it is on the cheap stuff. Is it because of the turbo / ecu linking up?

Sorry, Noob with a hopefully not screwed up car.
If it's similar to earlier models, I believe the ECU adjusts the timing and whatnot of the engine to accommodate the crappy gas. Your car will be much happier running what it was designed for.

Always trust the owner's manual over the dealership. The salesman at the dealer where I got my first WRX didn't know what the big silver finned thing on top of the engine was.
 
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