ok guys, odd issue and searching has brought up nothing for me.

heat works great. almost too great.

but when i come to an idle at say a light, the heat seems to die down. it'll start blowing luke warm air until i start moving again. if i give it a little gas while sitting, it'll get warm again, let it sit and idle, it gets cold again.

i read that this may be a partially closed valve in the heatercore thats stuck? any other suggestions?

 

Almost sounds like a partial blockage in the heater lines to me. I would do a complete coolant flush through the radiator and engine to push it through. The more load on the engine will give the cooling system more pressure to push past the blockage where as idling there is not enough pressure and although to coolant might be flowing through the engine it is not flowing through the heater lines and heater core

 

awesome, will try a flush this weekend. thanks for the suggestion!!

 

NP hopefully it fixes your issue.