I feel while driving on a long drive like 40 Km. AC cooling and fan throw reduces significantly, when i picked the bonnet tried to feel the aluminium pipe, it was all covered with ice, after a rest of 30 minutes with open bonnet, when i again started the car, the Ac started working efficiently, but after again travelling around 40 minutes Ac almost stopped working, the throw was very low inside the cabin.
The same happens on every long drive , do some friend have an idea why it happens , whereas AC mechanics say Ac is working excellent