Kia Sportage 2007: Diesel engine stalling issues

If the problem has been caused by bad fuel the repairs won’t be covered by the new-car warranty. While the fuel companies do have a warranty that would cover a problem caused by their dirty fuel it would be very difficult to prove it was the fuel in the first place, and it was a particular fuel company’s diesel that was the cause of the problem. I dare say you don’t have a sample of fuel you could have tested, or I’m guessing a receipt for the fuel you bought. It’s all too difficult. I would get another opinion before you spend the money on cleaning the fuel system.