If your sire that it happens when in a dive or you can make it happen, you can test it in the tower.
Open the controllers section in the game and select an axis with the scaling window open. Move your controls pretending that your going into a dive, or what ever sequence causes the spiking. Do it for each axis, brakes too. If you can do it regularly in the game you should be able to spot it in the window seeing your line jump.
Once you spot it, well then you have to decide whether to repair or replace.