Sputtering down the highway
I just bought a 2006 ford Taurus from my daughter and she said that it had been sitting for awhile. It had an 1/8th of a tank of fuel in it. I put fuel injector cleaner in it and filled it up. The car drove fine for a couple of days and now it’s sputtering down the highway?
Since the car has been sitting for a while the fuel that was left in the tank may be weak. Adding a half of tank of high octane to what is already there will help bring the octane level up. If the fuel is what is causing the sputtering then this should help. Besides, you have to put gas in it anyway so it is an inexpensive test.
The sputtering may also be caused by failing ignition components. If the check engine light is on, have the codes extracted and post them below for more details. A basic tune up may be all that is needed but make sure there are no codes first.