got a friend that has been have a issue with his 550 not wanting to start. I checked the plug wire even used a screwdriver to make sure the plug was getting a spark . this is where it get weird. when using the screwdriver it will crank right up while you hold it close to the plug which is inside still. Once we put the plug wire back on the plug its a no go.
he changed out the plug out later just to be safe and still will not start unless you use a screw driver to jump the plug wire to the spark plug.
what do y'all think it could be ?

thanks in advance

 

Anyone with any ideals ?