Took my car in for a trouble code P0171 lean fuel mixture which I know was the only code from my scan tool. He asked what symptoms I had. Told him the car was running rough and hesitating. I dropped the car off to have them look at it. They called me and said it would cost $430 for egr valve. I told him that I would call him back. He said hang on and came back with (I was looking at the wrong numbers it's $330) so I paid the bill and drove off. Taking off from the first stop it hesitated. Went back a few days later explained the problem. He said no time today we can make a appointment for you. I said , I'll get back to you. Went home and plugged in my scanner. Pulled a code P0301 no. 1 cyl. misfire which was not in there before. I carefully pulled plug wire no.hillips 1 off and found the boot broken inside the head. I'm the only one to work on this car in till now. I installed new plug wire car runs great. they need to fess up when they mess up.