I am buying an Acura RDX suv, and i mentioned to the dealer that it was a shame that premium fuel is so expensive. He replied that i could safely use regular in my vehicle, but i would lose a bit of performance. I would like to know if it will hurt the engine at all; i'm not worried about performance, but i want to take care of the engine. Thanks!

Be weary of advise from a sales person. Not all are ethical and they should be. If it says on your manual to put a certain grade of gasoline that is what you put in it. From experience I can tell you that if the manual says premium gasoline, you put premium gasoline. The reason premium is specified on certain models is because they are design to work with the high octane, and all the components from the spark plugs to the material on the head are design to withstand a specific heat capacity. With regular the vehicle engine has to be well built to the ignition fluctuation of regular gasoline. High performance vehicles or luxury vehicles rely on the constant ignition of premium to fully utilize a specific material either on the head or the block to produce optimum fuel and power performance. The reason vehicles that use premium are much more expensive is to offset the overall warranty cost to the manufacturer if the vehicle was to fail during it's warranty period. Most vehicles that use premium as soon as you put regular the valves will begin to knock and over time might bend or fatigue causing more problems. Another problem with using regular on a premium vehicle is transmission failure. Like you where told the loss of power is there, but it affects the vehicle in many ways from wearing down the alternator, to over wearing belts, reducing the performance of your air conditioner, improper cooling of your engine and the list goes on. Might not be able to see it in the first five years of life of a vehicle or while under warranty but as soon as it starts to need new parts you will start to see the cost of using regular. MY ADVISE IF YOU CANNOT AFFORD TO PUT PREMIUM ON A VEHICLE YOU ARE BUYING DON'T BUY THE VEHICLE. In the long run it will cost you much more...........

you can use any fuel you want. its your vehicle. the only problem is how it will run. Acura suggests using premium fuel but regular pump gas doesn't hurt. the premium is just cleaner and doesn't leave that much carbon deposit behind. Ive used regular fuel in my Acura and it runs good. suggestions are suggestion, it doesn't mean you have to listen.