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Premium vs regular

we just purchased a 2007 VW GTI turbo. do we need to use premium gas. will regular hurt the engine. the dealer told us regular is ok, but everything i read says that using regular may damage the engine

yes

yes to must use premium?

Read the owner’s manual. It will tell you for sure. Do not use fuel of an octane rating lower than the manual requires or damage to the engine will occur. Most turbo cars require premium, and the use of lower octane fuel for anything other than an emergency for a short time will damage the engine.

Also, www.fueleconomy.com lists this car as a premium fuel car.

Yes, you must use premium with the turbocharged engine. Anything else is asking for trouble. Big, expensive trouble.

Dealers will say anything to make a sale.

Yes, you need to use premium gas unless you want to inflict very expensive damage that is not covered by warranty. Why would it not be covered by the warranty? Because the Owner’s Manual states that premium gas must be used in the turbo charged model.

When you don’t follow dictates like the gasoline octane requirement, you give the manufacturer an “out” when you have the car towed in with detonation damage to the pistons. Why people fail to read the Owner’s Manual–especially for important issues like this–is simply beyond my ken.

Which “the dealer”. Not specific enough. If it was the service department, don’t believe it. If it was the sales department, double don’t believe it. This is such an easy decision. Everything read beats everything said.

The owner’s manual have the answer. If it says use regular use it. You will gain nothing by using high octane. If it “recommends” premium, you should use it, but you can use regular if you don’t mine loosing power and some mileage. If it says use premium, then failure to use it can damage your engine.

I believe that engine REQUIRES premium.

You asked a salesman something technical about the car he sells…That’s asking for trouble.

If you have the owners manual dig it out. Some VW with the 2.0T can use regular with degraded(usually slightly) performance. Also check the inside of your fuel door’s sticker. It will definitely state unleaded required but either state premium required or recommended.

If you cannot find your octane rating in your owners manual, sometimes the octane rating is inside the fuel filler door. I read some interesting responses to your post. My response will differ slightly from the others I read. I believe if you use an octane gasoline rated lower than the recommended flavor, your engine would have a tendency to preignite (Ping) IF, and that is a big IF, it didn’t have a knock sensor screwed into the block. The knock sensor (when properly working) will sense preignition (well before you hear it) and electronically retard the timing to prevent further preignition. This goes on continously. So in theory, you won’t see any difference in your car’s performance, with the exception of lower fuel milage and slightly decreased performance. So, with all systems performing up to par, you will not hurt your engine by using a lower octane rating, but your milage and performance will suffer. If you use a gasoline with a higher octane rating than necessary, you will not experience any increased performance or better gas milage, you will simply be supporting the oil companies and refineries in a better manner than necessary. The octane rating is boosted in the gasoline by certain additives that change the performance of the gasoline and its ability to prevent preignition. They do not make the gasoline “hotter” or “more combustable” or “burn cleaner” or any of that. That is all I have to say about that.

A nice reply benny. I would say it was very accurate. However I would not rule out engine damage for those cars that indicate they need high octane, even if they have a knock sensor. The computer can only retard the spark so far and in some engines the knocking may not be very noticeable to many drivers.

While it may not be very likely, the cost if it does damage the engine is well worth the small additional cost for fuel.

I guess checking the type of fuel required should be done before you buy the car if you are not prepared to feed a car high octane.