Heat blows cold if I come to stop!?

[digitalasylum7]

Ok so I recently noticed that when i stop driving, ie: traffic light ... my heat blows cold. Once I start moving it gets warm again. Any ideas?

 

[hun6over]

a/c fan isnt working?

 

[luvmygst]

Check and make sure the coolant is full.

 

[1gcrazy]

Check and make sure the coolant is full.

Spot on...


If the heater core isn't getting any warm water from the engine then it will only blow COLD air since it's april and thats the only air available.

I would double check to see if you have a coolant leak or you just havn't checked it in a while...

 

[Defiant]

It's also possible you have a failed impeller in your water pump, and are getting insufficient circulation when the RPMs drop.

 

[Locke]

May also check for a plug in the heater core. May prevent enough water from passing through during low rpms.

 

[Burnett03]

a/c fan isnt working?

huh??

check your coolant level, bleed the system for air pockets

 

[digitalasylum7]

huh??

check your coolant level, bleed the system for air pockets

As a matter of fact, a drive up to Vermont, I got to about Albany fron NYC, and noticed my temp guage started to spike. I pulled over and saw that my overflow tank was empty and smoking! It turned out that it somehow cracked and the coolant leaked out, I bought a new tank and everything is fine temperature-related now.
---- Could that have caused air to somehow get in, to the system, since for a part of the time the overflow tank was empty along with probably the radiator? Since changing the tank and adding coolant there are no temp spikes, but could that have caused some chain reaction to something else?

 

[HyperGSX]

i had the same problem, i was leaking coolant out.