Please help my car is overheating and I'm not getting any heat from the vents. Before this started I noticed the car was taking long to reach 90c so I thought it was a bad thermostat. After I changed the thermostat it started overheating and now no heat thru the vents. I checked for signs of a bad gasket but didn't c anything oil looks fine no blue smoke, took it to a mechanic he said it failed the pressure test but it doesn't show any signs of leakage, I nneka dont have to refill the reservoir