Check engine light on my 2015 Ford Fusion SE 1.5l started randomly coming on after filling up with gas, ran by a ford dealership I was close to and had the code checked. Didn't get the code but it was something for oxygen sensors. Decided to schedule an appointment for today to have it checked out. I will post the invoice they provided with a list of parts they stated the car needed. The tech said that the purge valve was stuck open causing excess fuel to be dumpedinto the motor. The excess fuel being sent through the exhaust caused the oxygen sensor code to throw. He said that it had caused my spark plug to have excess wear causing bad gas mileage, although the car has close to 100k miles so spark plugs need to be done soon anyway. The bill was for $1378. Just wanting some different opinions on more experienced folks. Does this seem reasonable or should I stay away from the dealer?