Question

is there more friction between a car and a road on a sunny day then a rainy day why

Answer 1

this is because when the rain the road becomes wet and it reduces the friction so there is more friction between a car and road on sunny day than a rainy day.
This happens because the water forms a layer on road and reduces friction,the water act as a lubricant on road.

Answer 2

yes there is more friction on a sunny day than a rainy day as there is some interlocking between the wheels of the car and the road as if it rains the water smoothens the surface and therefore there is not that much interlocking or grip between the objects