Using search I found another thread similar to my question...but it went nowhere. So here goes.

My 07 "S" heat cools down while at idle -stopped at a light for instance-. Thats not to say its cold.....just cooler than when I am moving. The fan speed stays the same while moving or stationary, so I know its not the fan. The antifreeze is full.

Could someone else living in a cold area confirm if their temp drops slightly while stopped, particularly when the heat is coming out of the vent?

I would hate to waste a trip into the dealership and take time off of work if I didnt need to.

Thanks.

 

I have a 2011 JCW that does the same thing. Maybe it has to do with auto climate control. Normally I leave the heat set at 62 and didn't notice it, but when I set it at 66 or 68 I sometimes notice it, but not sure if it happens all the time.

 

HA! I love your name.

Thanks for the reply......glad its not just me.

 

I've noticed that mine does this as well in the mornings before everything gets fully warmed up. I don't have auto climate control. I'm guessing it has to do with the thermostat slowly opening and allowing the rest of the (colder) coolant to circulate in the system.

 

That Pez name Rocks! My car seems to act this way as well. It takes a good 10 minutes just to warm up good in the first place.