evel knievel coil

just installed a new bumper coil and the game turns on but the coil get super hot and the flippers dont work

I would start by disconnecting the new coil and troubleshooting the flipper problem. Then take Ken's advice and check the driver transistor for the bumper coil that's getting hot. Assuming the coil is energizing when you turn the game on.
 
i unhooked the coil and the MPU led only flashes 4 times and stops . Bad MPU ?

The 4th and 5th flashes check the PIAs (6820 or 6821 at U10 and U11 on the MPU). That could explain your coil being locked on but I wouldn't say that's a guarantee just yet. You could swap the PIAs and see if you get more or less flashes. If so you can assume you have a bad PIA. Reseating the socketed chips might fix the problem. If so you've got some questionable sockets.

Was the MPU booting before?
 
it booted up last night after the coil got replaced but the flippers did not work . then i turned it off due to the coil locking on
 
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