Is putting "plus" gasoline in my car good, or bad for it?

Question

I have an '07 Chevy Impala, and I usually put "regular" in it. I decided to put plus in it for a change. I noticed I got better gas mileage, but did I harm my car at all?

Answer 1

you're not racing why put high octane gas in it???

Answer 2

Using higher octane gas then is listed in the owner's manual is a waste of money.

Answer 3

no not really if the gas was the same type

i.e (sorry I'm english) if the fuel was unleaded then the plus or premium unleaded will not harm your engine, but if you put diesel in the tank then you will be seriously harming you engine

Answer 4

No it won't harm your car,but you could be wasting your money

Answer 5

Unless your owners manual or fuel door specifically recommends using premium fuel you will not see a fuel economy or any other performance increase by using it.  1 or even 2 fills is not an accurate guage of fuel economy.  You have to average it out over several months due to small changes in driving habits (making or not making an extra trip here or there, etc.)  So do not let one experience fool you.