Q: Jerking reaction

Hi There, If the hose is still leaking causing coolant to be lost and the vehicle continues to overheat, this could potentially result in a head gasket being damaged causing a cylinder misfire, which may cause the jerking reaction you are describing. A blown head gasket may cause a number of different symptoms. A head gasket that fails between cylinders will generally cause a misfire and potentially compression leaks from one cylinder into another. Low compression will eventually result in a rough idling engine. When the head gasket fails between a cylinder and the coolant port, coolant may leak into the cylinder causing it to be burnt with the fuel charge in the combustion chamber. This often results in misfires on startup, especially after the engine is run, turned off and restarted. This type of failure may not always show with a compression test. I would recommend having an expert from YourMechanic come to your location to properly diagnose the vehicle.