hi there,i done the head gaskets on my95 wrx last week and every things to be ok,
but recently i've noticed that my temp gauge drops down to the cold side of the gauge when i'm giving it the guns,
it doesn't overheat and the heat out of the heater stays constantly hot and not using any water,
has anybody experienced this before
just want to put my mind at ease

 

Possibly the thermostat is sticking open.

In slow traffic it'll heat up to normal, but as soon as you start to get on the open road it'll drop.

You may notice the heater take longer to start blowing warm from a cold start, and the heater output, whilst blowing hot may not be as hot as it could be.

 

BTTT