When I start up the WRX and have it idling, when sitting inside I can hear water sloshing thru (I assume) the heating system. As i blip the throttle this sloshing noise changes as the pump pushes the water round the system faster - I guess.
Does it need bleeding of air? any ideas??

 

Air lock, do a search on here how to remove it properly. It can be a bit of a pain!

 

yes, when cold take off the cap off the header tank(next to intercooler) and start car and run up to temperature, the airlock will burp out of the top, you will see bubbles then top the tank if required.

 

Think it helps I you turn the heaters in the car up to full whilst burping it.

 

i get the same on mine..

will try the above

thanks.

 

+1