You can! However, you must ensure that you have both earth-fault circuit breakers and proper surge protection. Without these there is a risk of fire. But even then it's very slow, compared to a proper EV charger... Ordinary wall sockets and engine heater sockets are not adapted to the high load that charging an electric car or plug-in hybrid entails, at least not for a long time. With a correctly installed EV charger, you can charge your car quickly, safely and securely.