So my 2009 MO has started surging when the AC is on. I brought a recharge can at AutoZone and used the gage to check the pressure. everything was well within normal range. Today I took it to a local shop that did a vacuum and leak check and the AC was working fine after the removed some moisture. Once I got home and parked after a 8-10 min ride from the shop to home it started to surge again. could this be because where I live there has been high temps lately? should I do a coolant flush and see if that helps or check the battery. I believe the battery was brought in 2017. please help me out as i use this car to transport my mother to and from her doctors appointments. all help is much apricated.