Took the car in for an oil change this morning.. and was told my battery needed to be replaced: "How much?" "$150.00 +" "No thanks. Will the car start?" "yes" Drive away... 1 minute later, notice the engine seems to be running rough.. Pull over and call my buddy, we go buy a new battery for $100.00 at autozone, Replaced that, reflash the Tune to the ECM, no change. engine running very rough. Take it to Jones Ford in Shallotte, NC. Tell them what happened, and tell them it seems like the engine is not firing on at least a couple of cylinders. 5 hours later, they call back, they tell me my clutch is making noise and needs to be replaced for $1,500.00. My response: "Ok, Besides the fact that I didn't bring it into you complaining about a clutch issue or transmission problem, why is my motor running so rough?" Response: "Well. 3 of your cylinders are not firing" "Ok, the million dollar question is, WHY?" "We don't know. We would have to run addition diagnostics on the motor to determine that." "For an additional cost? No thanks." Pick my car up, pay the $100.00 for the useless diagnoses fee that didn't tell me jack ****, and limp the car home. Started to pull the Coil pack wires to see which cylinders aren't firing and discovered that its not 3 cylinders down but the entire passenger side that's not working. Checked plugs. a little dirty but ok. put in a new one just in case., swapped a coil pack from the Drivers side, no effect...pulled off valve cover, no damage to cam, or chain or gears noticed.. No error codes either... **Stumped** Blown Fuse? I don't have the equipment to verify passenger side timing, or fuel injectors... but can verify fuel in the fuel rail. Anyone know a Honest good mechanic near Shallotte, NC that knows an 05 Mustang GT?