260Z Key switch problem ON, START
 

I bought a 260Z from a guy who broke a key in the ignition. Instead of replacing the unit, he hot-wired the car. And the car started fine. Oh, he also put an MSD ignition system in the car. I purchased a new key switch. The car will turn over on START but when the key goes back to rest at ON, the car dies. If I hold the key in position in between START and ON, it will continue running. I have tried two new switches, same thing. Any ideas?? An ignition relay? Something to do with the MSD? I am at a loss. Can take it to an 'old pro' here in town but would have o tow her.

Does it still run fine if you just start it by the old way of hotwiring it like he did? Also when you bought the new key switch did it come with the piece that attaches to the back of it that the electrical connector comes with? After a while these switch cylinders get old and don't work well, but if yours is new it sounds like there might be an issue in the way it was hot wired.

New switch and connector
 

The key switch is new. It did run fine while it was hot-wired. A guy mentioned the ballast and coil. There is no ballast, i don't think. Could it be the ignition resistor mounted on the firewall inside? I have a wiring diagram but just can not imagine what is going on.