Just had my 2015 A5 2.0 TFSI Quattro serviced. Went to the local dealer as they have history with the car and I thought it would be good for the service book/ resale. Doh!. One job was to replace the coolant reservoir bottle, which had split( anyone else had this?). When checked later that evening a connection had blown off the bottle and 2 ltrs of coolant gone. Replaced both but found they had not replaced the o ring. They looked at the car a few days later and after reaching home I looked under the bonnet again. The bottle was now over filled to mmís from the top. When I sorted that out it now seems settled down. Anyone else had issues with the cooling system or possible dealer incompetence.