An outboard surging condition is usually due to fuel starvation. The fuel tank, hose / connectors, primer bulb, and or filter(s) are all suspect, and should be checked. Also possible, carburetors and fuel pump.
a surge of testosterone in males and it causes ovulation in females.
The storms surge
#1 power surge
Low pressure also contributes to the storm surge.
Check your vacuum lines this usually the cause for a surge in engine speed when idling or running.
a vacuum leak.
You may have a pull on your batt, or a surge.
Probaby a sensor.
Rotors are out of round,need to have them turned.
It is possible it is one of the speed sensors.
tsunami, tidal wave or a water surge.