[Bobby D.]

I'm a newbie waiting for my Cooper to be built. I understand that even the 1.5L needs premium gasoline. I have an MGB with an HC engine that takes premium. On occasion, I've run into stations that I suspect are cheating with regular in the premium pump. Has anyone run into this situation? What happens to a Cooper running on regular gas?

Bobby D.

 

[02fanatic]

I always seek out Sunoco for premium fuel....you won't ever have a problem there.

John

 

[sirron]

I always seek out Sunoco for premium fuel....you won't ever have a problem there.

John

Yuk - Yuk.>

 

[02fanatic]

Yuk - Yuk.>

Really? Where can you find Ultra 94 (Octane)?

 

[Another Mini]

Premium gas is recommended, not required.

 

[siriuszero]

Premium gas is recommended, not required.

No, but you don't want standard gas in your tank either. It will knock and eventually cause damage to the engine. Mid-grade (89 octane) is minimum and premium, in my experience, will give you the best performance and mileage.

 

[Tiger]

What he said. Don't mess with it - feed it premium. The computer will compensate for bad gas to a point to keep it from knocking as much as it can, but in spite of what many will say (and I've read a bunch of people saying, "Ohhh that's hogwash, it'll run fine on silver or just plain old unleaded...") don't mess with it... the engine is not running normally.

And yes, there are some stations that will cheap out on the gas to provide a "discount", but for the most part the regulations and regular inspections keep them pretty honest. I refuse to pay the incredible prices by some of the big boys here (Chevron, Shell, Texaco) and have been doing fine. Of course, I'm also tickled to be getting so much better than my truck and running the calculations, I'm still saving money even buying premium with the mileage I'm getting, so that takes a lot of the premium price sting away.

 

[dirtyscarab]

Guys, this might help, from edmunds.com:

"Edmunds has compiled two lists: "premium recommended" and "premium required" for vehicles from the 2009-2014 model years (with a few 2015 model-year vehicles). If your vehicle is on the "premium recommended" list, you're OK to try switching to regular unleaded gasoline. If, on the other hand, your car is on the "premium required" list, then you have to run premium fuel. You can confirm the information on these lists by checking your owner's manual".

Mini Coopers are on the 'Premium required' list.

Full link to article here:

http://www.edmunds.com/fuel-economy/to-save-money-on-gas-stop-buying-premium.html

 

[Evlkarl]

I have been running 89 Octane on my last Tank all City/Highway Driving before that I run a Tank of 91. Honestly I can not feel the Difference so the Computer must be doing a good Job. No Matter if I use 89 or 91 Octane them other Motorists still drive like Knuckle Heads around me. However I will stick with 91.

 

[jamesahy]

I'm glad our nearby value supermarket sells 95 oct reg and 99 oct premium. Good old Blighty.

 

[swearingino]

It only costs me $25 to fill up with premium around here. No complaining from me.

 

[Another Mini]

From the MINI owner's manual:

"Recommended fuel grade
MINI recommends AKI 91.
Minimum fuel grade
MINI recommends AKI 89."

Note the word "recommend" - 'required' is not there

 

[siriuszero]

From the MINI owner's manual:

"Recommended fuel grade
MINI recommends AKI 91.
Minimum fuel grade
MINI recommends AKI 89."

Note the word "recommend" - 'required' is not there

Sure, but why not spend the extra $0.10/gallon, that's $1.10 to fill it with premium and make your car happier?

 

[Burning_rubber]

It only costs me $25 to fill up with premium around here. No complaining from me.

You are so lucky in the US

We have the choice between 95 octane and 98 octane in Europe but it costs me around 50€ to fill the tank and I'm lucky to live in Belgium where prices for fuel are relatively low compared to surrounding countries.

 

[MiniMpi]

We only have 95 octane here in Ireland sadly

 

[Burning_rubber]

Besides the price there is no noticable difference between 95 and 98

 

[Koryak]

The US 91 AKI is about the same octane as UK & EU 95 RON. Just a difference in how it's measured. The MINI's engine decrements the ignition timing if its knock sensor detects low octane so no real danger of damage unlike the OP's vintage MGB with high compression!

 

[MiniMpi]

Anytime I visit the UK I always fill up straight away with the 99 octane Shell V Power. There is an instant difference in the running of the car, even the idle.

 

[AarnMunro]

In Italy only 95 octanes.
I have tried 91 and 95 in france...sometimes 99 here and 100 in Swisse...no difference at all but the price!
It's my fault, probably I'm not able to feel the difference of 0.85 HP between 5000 and 5500 rpm that high octane gas can give...

 

[annoyingmouse]

knock is something that CAN happen. You are not guarantied to knock on low octane fuel, nor are you guarantied not to knock with high octane fuel. I run 89 since it's what Mini lists as minimum, but it's perfectly conceivable that someone's engine is doing fine with 87 especially if they don't regularly visit the top half of the rpm range.

Your engine is ignorant to the fuel you put in it. It simply runs normally until a sensor tells it not to.