Heater blowing cool at times.

[Danny-G]

I've been using the heater almost everyday this month and everythime I stop at a light or sign the temperature gets noticably cooler, like its almost at cold. What would cause this?

[kimokalihi]

Probably a clogged heater core. I'd imagine at a stop you're at significantly lower RPM and with the heater core partially clogged it would probably only be pushing enough coolant through the heater core to put out hot air at higher RPM. Try flushing it out.

[Danny-G]

How would I flush it out and does it involve taking the whole dash out?

[subydaddy]

Your coolant is low. Mine did this too. Just replaced the radiator yesterday.

[kimokalihi]

Check your coolant. If it's not low then flush it. Remove the hoses from the heater core (there's two coolant hoses that go into the firewall under the hood) and hook up a hose to it and turn it on full blast. I don't know any other way but there may be a better method to this. I'm drunk.

[subydaddy]

I don't know any other way but there may be a better method to this. I'm drunk.

Hahahaha, that should have been my senior quote... priceless.

But yes, check your coolant, it's probably low. If not that do what the drunk one said.

[Danny-G]

Well the coolant is definatly low now, over heated while out on a steep trail. So I'll fill it with coolant and see if that fixes the problem.

[beanis05]

You have an air pocket in the system I had this problem to it would take forever to warm up and would go to cold at stop lights and would come back at to heat when driving but would only work on full heat when driven hard or on the highway. If you are going to be doing this you might also want to check the water pump and thermostat it wouldnt hurt to replace them if they have not been serviced. You never know better safe then sorry.