I have an electric start Timemaster, 4 years old. I keep it clean and had it services at the beginning of the mowing year (April).Yesterday after cutting the lawn, I turned the key to off but the mower won't shut down. I unplugged and reconnected the wiring harness from the switch, but same result. I also checked the fuse (looks OK). I have to pull the spark wire off, which is a little shocking. I had my local Toro dealer order a new ignition switch but I'm wondering if there are any other suggestions why the motor won't shut down when the key is turned to off. Thanks.