Bax, this is what I have found so far.The right glow barely glows with the on board glow. If I use my hand held driver it glows nice and bright. The left glow plug works fine, that's the side were the on board glow is grounded. I switched around the positive wire from one plug to the other and I get the same result. It's as if I'm loosing ground contact through the engine. The next problem I think I have with the right cylinder is that it's possibly not drawing fuel. I would think that since the glow plug isn't lighting the fuel that raw fuel would be pouring out the exhaust but I get nothing but air. This is the same motor and glow driver I had in my Top FLite stinson and it ran like a sewing machine, now nothing but problems.