hi hope someone can help me with this query. i changed my thermostat and antifreeze today because my car was running cool now the car temp sits at 90c and the oil tem about the same which is a vast improvement the problem now is the system is not presurising and the expansion tank is staying cold. i took it on the motorway and gave it a 15 mile run in the fast lane got back home and checked the levels the radiator pipe at the top was hot but easy to squeeze and the expansion tank was stone cold the car seems to be running great all temps appear to be where they should be. i am stook for ideas any help would be appreciated