Re: Synthetics: When they do (and don't) help mileage
No, it isn't, but keep in mind that the gasoline you're using is a winter blend, which will automatically decrease your MPGs. Also, colder temperatures will cut into the fuel efficiency. Not sure what the temperatures have been where you are, but if they've been cold or colder than usual that will cause a drop in MPG's.
A lot of people's driving habits change during the colder weather, ie letting the car warm up, leaving it running while going into a store for a coffee, using drive thru's etc. If you're doing that you're basically getting 0 MPG's while the car is idling.
Finally, you should check the conditions of the spark plugs, air filter, tire pressure etc. Maybe you need a tuneup.
The fools, the fools the fools! They have left us
our Fenian dead, and while Ireland holds these
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