When accelerating at highway speeds there is a significant power lag when the vehicle switches from between the internal combustion engine (ICE) and the electric motor causing deceleration in the vehicle. This is typically followed by a sudden surge in power causing rapid acceleration. This causes unpredictable speed and makes merging onto highway traffic difficult. When this issue occurs the ‘Service Hybrid Electric Vehicle System’ warning lights illuminates. After several miles, the warning will turn off, but this occurs off and on when changing lanes, merging, or braking in heavy traffic. This typically only occurs at highway speeds when the vehicles transfers between ICE and Electric power frequently and has not been observed at normal city street speeds. The sporadic acceleration performance makes this vehicle dangerous to drive at highway speeds unless the electric motor is turn off. The car has been returned to the dealership numerous times to address this issue as it is still covered under warranty. However, they have informed us that ‘The code present in the car is currently under investigation by Chrysler. The Chrysler representative told us not to change any parts until Chrysler makes a decision on a potential recall.’ Despite repeated calls with Stellantis / Jeep customer service who promised us to expedite parts to the dealership for resolution, we are stil left driving this unsafe vehicle. This problem arose within 48 hours of the battery recall maintenance being performed and has been recurring ever since the repair.