rwheelz

iTrader: (2)

99 GS400, I drained and filled my coolant today, and want to be sure all of the air is out of the system. The repair manual says to open 'the heater air valve' but doesn't show where it is. I did the best I could with the loose rad cap method.

lyonkster

I would assume that "opening the heater air valve" simply means allowing water to circulate through the heater core, which can be done by turning up the heat with the engine running.

rwheelz

iTrader: (2)

well ok I did that... on some cars there is a bleeder screw at the front firewall to bleed the heater core, so that is what I was looking for.