My car went through a full service at a well known high street garage on 6 April 2010. After this, I noticed the fuel consumption increased significantly and the fan was staying on for longer than normal after the engine was switched off. I alerted the garage to this fact on 12 April and it was returned to them on 20 April for a check up, and they advised changing the fuel filter might alleviate the problem. It didn't, so on 17 May I contacted them and returned the car for them to check again on 21 May. After they checked the car they phoned to say that an engine management problem had occurred that they couldn't fix, and I would have to take the car to a main Ford dealer. I took the car (now in limp mode with very reduced power) to a Ford garage. They had to correct a fuel particulate problem which also had caused damage to the catalytic convertor. The bill for this was £1300. I took the car back and it broke down eight miles from the garage with a new engine management warning. The car was returned to Ford, where they fitted another new fuel filter. I picked the car up again and after approx 150 miles over two days noticed a very hot oily smell. A roadside recovery service came out to look at the car. They found that the car had been overfilled with oil by two litres and suggested that this could have caused the fuel particulate problem and broken the catalytic convertor. Ford took the car back for a courtesy check and have stated that the car seems to be fine now, but I want to know how I should go about complaining about the £1300 bill from Ford that I think was a result of the service done by the original garage. The service and associated work cost £500. The work by Ford to rectify problems most likely caused by car being overfilled with an extra two litres of oil cost £1300. Both garages deny overfilling with oil. I was inclined to think it may have been overfilled during the service but would it have still been able to function with this much extra oil in it? I hope you can advise, as currently I have both garages denying they have done anything wrong and no one admitting to putting too much oil in (although Ford admit they may have failed to check the oil level correctly). I look forward to hearing from you.