Im trying to build some coils for a friends car. Iv installed the new capacitors and my Strobo Spark tester say the capacitors are bad. I have had the caps in a box in my garage sense 2012. Is it possible they have gone bad from sitting 6 years?

Heres the caps I'm trying to use, I bought these from Langs back in 2012. These were left overs from when I was building coils for both cars and hit and miss engines, As I remember they all worked good back then.

Will, did you remember to open the points and insert a small piece of paper to insulate and then test the capacitor.

I will assure you that capacitor cannot go bad.