My 2014 Volt has exactly the same problems.
My 2014 Volt has exactly the same problems. Clicking noise coming from front axle when stopping/starting. Also no heat in EV mode only. 42k miles. Out of warranty. Volt with similar heater problem is being worked on waiting for pump part number 13597899. It's on backorder. Service advisor says sometimes a backorder means there is an issue with the part and a new part number will replace it. He recommended that I wait but this is a cold winter so I'm not using EV mode much. Very unhappy and am planning to communicate my feelings about GM to everyone. I've talked others into buying Volts but now I feel guilty. Sales and service has been an old school low class experience compared to their competitors. Please keep this thread updated with any solutions you discover. These are defects that should be covered for free even after the warranty period has ended.