maintenance thru cavalier ford in chesapeake can not find a problem please help

Start by going to another shop & have them look at it. The maintenance shop at the Ford dealer here is inept. l have a Ford Focus, 2002, & some a-hole ripped the passenger door handle off. We took it there to have it fixed. They said they needed to order a lock cylinder to complete the job, so they did not start work. Well, the geniuses did not notice that the only door that has a keyhole is the driver is side, there IS no lock cylinder on the passenger side. The dealer is not always the end-all when it comes to maintenance.

your going to a dealer to find problems sorry not a good place to go unless no one else is open id say its in need of a tune up or a full system flush coul dbe your not using the gas the car wants not all gas is the same for sure a better shop and autozone scans for problems for free

That is below average.
How are your driving habits?
Tire pressure good?
No extra weight in the vehicle? (like 100lbs?)
Oil level correct?
Do you only do stop and go driving all the time?

l am sure you're to the dealer because it is in warranty. Contact ford motor company about the problem. Do not l repeat do not take it to a private shop. You will have to pay them and it will void your warranty.