Bought a new 5-pack of 0.5 coils. Pulled the old coil and screwed a new one in, no smoke. Tried another, same thing. It's like it's not making contact. I did notice the tip that makes contact with the base is shaped differently than the old one and has more holes (the old ones had one hole straight through, the new one has two cross-holes). What changed? What do I need to do to make it work?