My 2008 Colorado starting throwing the codes P0351 (Ignition Coil A Primary/Secondary Circuit Malfunction) and P0301 (Cylinder #1 Misfire). I'm at a complete loss at what may be causing this, I have switched the #1 coil with the #2 coil and the misfire did not follow the coil. The problem...

So heres the deal, i took my '06 truck into my mechanics last weekend cause i noticed that it was idling rough. They determined that the seals on my heads were bad and i had them look up the description of the cylinder head service bulletin and they said that is what the problem was. My truck...

So my 06cc has about 105k miles on it... Just took it in today because it was misfiring again and they said i need to have coil pack numbers 3,5 replaced... and they already replaced 2,4 maybe 6 months ago. Is this common or is something wrong that is causing this to happen?