I have a 2001 Volvo Penta 3.0 GSP-A . While trying to see if I had spark (I did) I happened to notice that there was continuity between positive and the engine block. I also had continuity with neg to the block. Then a few minutes later i didn’t have continuity with positive. Then I did. Etc etc. I’ll borrow someone else’s voltmeter tomorrow to make sure it wasn’t mine acting weird, but right now I’m assuming I have a sporadic short ? If so…how would I even go about trying to find it?