NMW1982

Is premium gasoline a requirement or a suggestion for the Q5?

Will I harm my engine or cause "knocking" if I use lower grade gasoline?

Has anyone driven their Q5 with lower grade gasoline and not experienced any problems?

I know someone who has used only 87 octane gasoline for their A4 and has had no problems whatsoever.

soonerfan

There is a lot of info on the subject in the Forum archives if you care to search. Audi recommends premium fuel. One can use a lesser RON fuel, but it is not recommended. The ECU will adjust to a certain extent on timing, etc. but you will not achieve the MPG or the performance that the highest grade of fuel you can buy will give you. For the few extra dollars you spend for Premium Grade fuel, be it 93 or 91 octane (US) the benefits of increased mileage, response and peace of mind is worth it, and may be a push, dollar to dollar. Here in Oklahoma we have the luxury of being able to buy 100% gasoline and are not forced to buy an ethanol blend of any %. One can feel the difference in the seat of one's pants and mileage.......not to mention no degradation of seals, fuel lines, etc.

FitzLA

On my first Q5, I used premium and then switched to middle. Never noticed a difference, even on fuel economy. And what you would save in fuel economy by using premium, you would spend in the difference in price. Negligible difference. I've only used middle grade on my '10 Q5, and it's been completely fine.

hmn4858

Audi recommends 91 and up. You can use 87 with reduced engine performance. Anything below that and Audi says you can wreck your engine. A manufacturer recommends something for a reason and I dont' think Audi is in bed with the oil companies. In a 40K+ car, I don't see the point of trying to save a buck by going with a lower grade but to each his own.

The G Man

I dont understand why people use mid grade, its only 10 cents difference, you only save a $1.50 on a fill up.

rs4-380

all modern vehicles have knock sensors that will pull timing to compensate for lower grade fuels. Running 87 will NOT ruin your engine. What it will do is reduce peak power output and reduce gas mileage.

Huey52

Exactly.

kleinbus

I have used 91 all the time.

What is this fuel price drama? You guys buy 40k car, complain about few pennies and barely drive the car anyways...

FitzLA

Because I don't see a difference in performance or fuel economy, and I don't really care. I lease my cars and get new ones every 1-2 years, so I'm not worried about long term, if it even has an effect. The $$ is not the point. I just don't see a use for it. The only thing I do care about, if the brand. I only use Shell or Chevron.

The G Man

You dont think that constant slight knocking and retardation of timing will hurt an engine over time? This cycle happens over and over again when using the low octane gas. At the very least, timing retartdation will create a incomplete burn cycle, this will cause carbon build up, especially in direct injection engines.