I'm new to this site. Just had #8 coil replaced on my 2000 tundra and $500. later (and actually 2 weeks later) I have the same problem with check engine lite and misfiring. I took it back to garage and they want another 400 for 2 more coils put in. I kinda watched them put a new coil in #5 and engine sounded good. They said # 6 would go out soon. So without spending another 400 I had them put my old coil back in. Now to the help I need!! Where is the best and most inexpensive place to get a coil? And to replace it, is there just like a set screw holding it on and does it just slide in and plug onto plug? My spark plugs have 15,000 miles but that same garage put them in so I suspect they are not the best plugs. How long do plugs typically last and when I replace them what are the ones most people put in tundras? Any help is greatly appreciated. Thanks so much for your time!!

Mike