02 ls overheating problem

[pooh77095]

hello my tempeture gauge rises past half when i turn on the ac and it will start to boil over ive had fan changed with a used one switch hydraulic actuator changed thermostat and housing changed radiator tank changed and flushed and the degas bottle idk what else to do but like i say it only runs hot when i tur on the ac can some one help o and system has been bleed also today when i turn the car off i heard a whining noise on yhe passenger side by the left tank of the radiator