Quick Question regarding Ignition Coil!
 

Hopefully this isn’t too confusing and sorry if my wording is off, but trying to explain it the best I could.
I added pictures to make things a bit more clear.
Car: 2003 Mazda Protege5; 2.0 Liter… 4 Cylinder

This is my mom's car and she got a code that references a few different items, once of which was the ignition coils. I did some research and some people say it is common on these cars that they go bad and need changing. Luckily it is around the tune up time for my mom’s car so I will be doing spark plugs, ignition coil, pcv valve, wiper blades, stuff like that. But regarding the ignition coils. I was planning on buying the full coil (need two of them for this car) See the part I am talking about in the picture attached that is labeled (Picture 1).

However, I bought a package since I needed the other 2 coil boots ( I believe they are called) that have wires coming off them (See Picture 2) that connect to the main ignition coil piece (Again, Picture 1), but they came with 2 extra pieces which is what makes up the lower half of the main ignition coil.

I was just wondering if in the scheme of things when it comes to ignition coil giving problems, does the upper half of them where the wire harnesses are located go bad, or the 2 extra pieces they included in the package I got which just need to be swapped out go bad more? This way it will save me like $60 from having to buy the entire thing, instead of me just replacing the bottom portion.

In Picture 3, it shows in the red circle how it connects the top and bottom part, with the spring in the middle, so it doesn’t look like a big deal at all.

Would be awesome to have any feedback. Thanks a bunch.



Picture1
http://www.zerohourmetal.net/Picture1.jpg


Picture2
http://www.zerohourmetal.net/Picture2.jpg


Picture3
http://www.zerohourmetal.net/Picture3.jpg

Replace everything for piece of mind and knowing it was done right.
Don't know specific problem for that P.O.S.

I think Noggin is right. I follow the Lincoln LS forum and they have always trouble with Coil On Plugs. Their recommendation is to replace all plugs after gapping them right and replace all COPs at the same time.
This design is a bit different in that one coil is firing 2 plugs. To me this is an additional reason to replace all 4 plugs. Make sure the gap is right, and replace all coil packs and wires together.
Otherwise you will be under the hood again and again.