Bought this for my 2002 Ford Thunderbird, lived with her for almost 2 years and one day she started to drop out. I've read all the information you can find online (not much) and it all came down to one of the few things, bad coil, bad spark plug, leaking gaskets, or all of the above. Yes, it's that vague and I didn't get the check engine light to tell me which cylinder was affected. After removing the spools I found oil on them so the gaskets are a tough job trust me but these new ones fit perfectly in those spots, I just wish a sheet of paper would come to say which bit goes for what is as some of them sometimes scratch your head like so many bits are similar. Tip: If, like me, you find that the old ones are either missing (yes, a cylinder gasket was missing, that's a mystery) or melted goo, it's fine to clean. If you have this machine and a similar problem and need more advice please message me or comment on this review.