Originally Posted by twolitrepinto

if the electric fan is working it wont matter about the intercooler in front of it, the air will get dragged there anyway by the fan. must be something to do with rad tho because turning the heaters on is cooling the engine. in effect the heater matrix is doing the radiators job.

make sure there is water getting to the rad, check all the rad pipes are getting hot and feel the rad itself. make sure the fan is cutting in when it should.
is there a small return pipe coming from the top of the rad to the water bottle? if there is check this is not blocked because its a self bleed mechanism to stop the rad airlocking.