You never pull a plug wire off while the engine is running.
Not only can it cause you to wet your pants involuntary, it may also fry the coil.
Tester
2 Likes
Never thought it could damage the coil. Thank you.
Not disputing Testers post…
Never hurt an ignition coil on a distributor system by pulling the wires off with the engine running, and they make insulated plyers but yeah it bite ya if not careful, but you normally keep it close to the engine so it will release the energy (spark) on a bolt or stud or about any grounded metal, harder to do on DOHC engines… Once you get into distributor less ignition systems the coil(s) seem to hit a little harder, and not recommended to pull the wires, OBD2 systems shouldn’t pull wires or COPs with out them being properly grounded for the checking spark… I have an old GM spark plug set at like 0.080" gap with a ground wire attached to it that I use…
My fun car has a MSD ignition system that at idle fires multiple times per rpm with a 50K volt coil, it will knock the c.r.a.p out of you if not careful, I’ve been bit by it a few times, hurts like ■■■■… lol
But best for the DIYer to not pull ignition wires off while the engine is running…
Me, after pulling the coil the to distributor cap wire while engine was running when I knew everything.
Tester
1 Like
Yeah my coil wire has lite my world up while checking my transmission fluid level, I started wearing a long welding glove when reaching down to it… Don’t know what idiot (me) thought it would be a good idea place to mount the Super Coil on the inner fender… lol