[mikesz]

Personally I would replace ALL coil packs. Easy job. I was having same issue not sure of the CEL codes I was getting but I bought 2 coil packs that were throwing CEL. They LOOKED fine. I then decided to replace the rest. Left bank cylinders were throwing the CEL right bank was not. When I replaced the right bank coil packs I couldn't believe the cracks in them! While you are in there you may want to replace spark plugs and tubes and seals. Also if you choose to replace tubes I would go with OEM they are more robust than aftermarket ones.