Just Measure it. As a proper car guy, I assume you have a digital multi-meter. Just follow Fluke's instructions. https://www.fluke.com/en-us/learn/b...M7b0aWSpzzxr8X7SB88ktkmGIlUePBD9FP2HQZqR4C-Th
Current thread by @tubman and he’s using .22uF https://www.jalopyjournal.com/forum/threads/condenser-guinea-pig-needed.1340088/#post-15681390
Big difference there guys between 22 mf and .22 uF! About 100,000x in fact. 22 mf (milli-farad) is equal to 22,000 uF (micro-farad). One will zing you pretty darn good, the other not so much.
...and to add to confusion, old electronics capacitors sometimes were marked MF for microfarad. Normally, a big M is for mega = million. Anyway. As others say, around 0.22µF/220nF seems common. I measured an old Bosch one at just over 250nF yesterday. It isn't too sensitive.