Your gauge is probably just stuck at 27 PSI. The cycling on and off has probably busted the bladder in the pressure tank, which makes the cycling on and off worse. Then the cycling on and off is probably causing your overload in the motor to trip, which will reset itself after a minute or two.
I am guessing gauge is broken, bladder tank is busted, and pump is on it's last leg, all because of cycling.
If I am right, sorry! But I have seen it too many times.