Is it safe to jump start a car while the engine is running?
Is it safe to jump start a car while the engine is running? The reason for 2, if battery cant absorb energy, removing jump leads can lead to a voltage spike and this is of course harmful. You would have same effect if you disconnect the battery of a car while engine is running. So, it is safest to charge the empty battery and then restart the car on its own power. Why is the battery on my JumpStart not working? It will not last forever. At some point, usually between the three-year and five-year mark from new, your battery...