My daughter is interested in a 2001 S40 Turbo. My question is if it is necessary to run premium fuel in it, and if she doesn't what harm will it do?

Also what kind of mileage can she expect to get? By the way it is an automatic.

Thanks in advance.

 

Although I am a brand new S40 owner myself, I have had a few other turbo charged cars, and it is very much suggested that you use premium octane fuel in them.

 

Do you still have the owner's manual? What does it recommend?

I just bought a 2009 S40 T5 AWD...the manual recommends premium but does not require it. I appear to be getting slightly better mileage (1.5 MPG?) with premium, so I'm going to continue using it. If gas prices shoot up again I know I always have the option to go back to 87 octane without hurting the engine...

 

Just to clarify my response, a turbo engine, by design, compresses the air going into the engine, as opposed to normal engines in which the air casually strolls in. This makes things inside the combustion chamber much more sensitive, that is why it is more important to use the recommended fuel level in turbo engines than regular engines. It is true, in many engines that are well built, you can get away with using mid grade periodically with the danger of premature knocking, but there are many small turbo engines which require premium whereas some much more powerful V6 engines that don't have a turbo recommend regular.

So for the S40 being a 4cyl. 1.9T, it is, like I mentioned, HIGHLY recommended that you use premium octane fuel. Again, being that I have just recently purchased my 2001 S40, I am not all that familiar with the specifics on Volvo motors, but with the other vehicles I have owned that had turbos, you are likely to run into issues down the line if you use lower octane fuel too much.

In my VW GTi knocking occurred after a while as a result of my wife using 87 octane. In another turbo charged GSR that I had I only ran 92 and had no problems at all. It really does have to do with the motor itself and the specific build of it, but its better to be safe than sorry.

 

Ok, premium it is!

Now about what kind of mileage can she expect with normal driving?

 

Sorry, I personally cant help you there as I myself am a new S40 owner myself, but I would assume an average of low 20s...