The pin is activated by a spring loaded flyweight on the cam, The spring can weaken or break causing intermittent ACR operation.
They should Ohm test the coil and igniter, Either could be out of proper spec range and cause hard starting at cranking rpms but run fine at higher rpms.
I didn't see your post before the PM......
Originally Posted by piston slapper
You never learn anything until you admit you don't know it all...
"Why go out preserved when you can go out beat up, worn out, sliding in sideways screaming, Holy Sh!t What A Ride" !!!