I have a 2016 XC60 with a little over 60k miles on it. Over the past three weeks every now and again while driving I get an engine overheating warning and the engine tempature raises until I pull over turn the car off and back on. It doesn't happen all the time, about once a week. I checked the coolant and noticed it was below the min line but after I opened the coolant lid it made a decompressing sound and the coolant start to raise back to above the min level. A obd2 scanner reads back zero errors. Any idea what it could be would be greatly appreciate? Thanks in advanced.