This is what many of us did. Replaced all 8 coils for under $150. When the dealer replaces JUST the one that shows up as bad? Within weeks, another old coil often fails intermittently. It drives you crazy, and may or may not show up on their computer as being bad. But it is. So you get hit with diagnostic time, and no repair. Until that coil FINALLY triggers a CEL light.
sooo..what many of us have done, is just replaced ALL the coils when one acts up. For $114, thats cheaper than one hour of diagnostic labor at the dealer.
http://cgi.ebay.com/ebaymotors/NEW-...ptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories
Not to scare you off or anything from the ebay post but I bought the coil set from them (8) and installed them all.. one was bad so I just put in one of my "old ones" in replacement. But all other coils are running fine, just the one was bad..