So I bought an airplane recently. It came to me with a 2100 2s lipo on the ignition. I was having trouble getting the engine to start, and while it was sparking, I looked at the ignition module and saw that it was only rated for 4.8-6 volts. I disconnected the lipo and installed a 4 cell 2000 nimh pack. The pack was fully charged, and was in good shape. Now I have no spark. I've checked to ensure I did connect the pack properley, the polarity is good, and there is a light in the switch which comes on when you turn the switch on. Has anyone ever heard of an ignition module getting "dependent" on higher voltages? I havent had the chance to switch back to the original battery and recheck, hopefully this morning I can sneak out to the garage for a few hours of fun.

Thanks!