Is it worth the money to buy the high octane/most expensive gas?

Question

or can most cars get by on the regular? What about those additives that supposedly clean your engine? Is that just marketing bs?

Answer 1

Most cars don't need the higher octane fuels.

If the manufacture states

Premium Fuel "Required". You must use premium fuel to prevent damage to the engine. It means you have a high compression engine and the premium fuel prevents what is classically known as knocking.

If the manufacturer states:
Premium Fuel "Recommended". You do not need to use premium fuel. Your engine has a knock sensor to prevent knocking. You may see a slight power loss/mileage loss using the cheaper fuel, but it won't hurt your engine.

Higher octane fuels don't necessarily contain more "cleaning" additives than lower octane fuels. Octane ratings have nothing to do with the amount of cleaning additives to a fuel.

Now the explaination:

Higher octane fuels have a higher resistance to something called pre-ignition. Basically making it harder for the fuel to combust until it is ignited by the spark plug. Actually that is what is meant by the octane ratings, it's a measure of how resistant a fuel is to ignition.

Using fuel of a higher octane, typically will not hurt your vehicles engine, while using a fuel of a lower octane will cause what is known as "Engine Knock". An engine that has high compression, will actually have places inside the cylinder that is hot enough to begin the ignition process that is at a point other than the spark plug. These points of pre-ignition are typically where the piston and cylinder walls meet. This will cause a flame front to start at a point other than the spark plug. If the flame front when the spark plug starts will eventually collide with the flame front generated by the pre-ignition. When these flame fronts collide, you'll get the shock waves. (and you'll hear these shock waves in the forms of "Knocking") These shock waves over time will do internal damage to your engine.

If your owners manual says "Premium Fuel Required", it means no knock sensor has been added, and you must use the higher octane fuels to prevent engine knock. If you're owners manual says "Premium/Plus Fuel Recommended", it typically means you've got that knock sensor that will basically tell the electronics to retard spark and minimize/prevent knock by igniting the fuel at a point that is less than optimal, but preventing engine knock/damage.

Answer 2

Buy the lowest octane you can that doesn't cause knocking in your engine (you can hear it -- it sound like a ping or someone knocking on a metal door). If your engine doesn't knock with the lowest octane, then that's what you can buy.

There is no such thing as cleaning an engine. The cylinders are as clean as they are going to be whenever the engine is running. There are some additives that keep fuel injectors cleaner (in my experience), but only in high concentrations (i.e. adding a whole bottle to the gas tank), not in the miniscule amounts added to the underground gas tanks at the filling stations.

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Answer 3

Unless your car is designed to require high-octane fuel (and if it isn't a sports car/performance model that probably isn't the case), no it generally isn't worth it.

There is only one situation in which you should run premium gasoline in a car that calls for regular: If your car is knocking or pinging on regular (due to carbon deposits or bad seals, or whatever), higher-octane fuel can reduce or eliminate that, and act as a temporary fix.

Other than that, no, you should buy the lowest-octane that meets manufacturer specifications for your car.

Answer 4

New cars come with a fuel octane recommendation, there is little or no benefit to useing a higher grade fuel than what is recommended. I think it is a good idea to use quality fuel at a reputable service station. I personally add Lucas fuel stabilizer to my tank when i change my oil to help keep the fuel system clean.

Answer 5

in my view, the better the cost of gasoline is going, the greater desirable the cost of the better octane gasolines. the rationalization... the variation in value in the path of the years has been continuously 20 cents. If the cost of a gallon of unleaded popular value $2 and the top rate grade gasoline value $2.20 you're able to go with to work out close to to ten% greater desirable mileage and/or overall performance. whilst the cost of Reg unlead at present value $3 a gal, the top rate value $3.20 and now you're able to might desire to get in basic terms 7% greater desirable mileage and/or overall performance to justify the cost. by way of the way, i think of that the greater desirable overall performance you get isn't figured into the reductions.

Answer 6

No. If your car wasn't specifically designed to use that type of fuel, it's a waste of money.

Answer 7

No, you should but the best octane that's available for the best price.