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2009 LT Avy heat issue

guttersnipes199

Full Member
Joined
Dec 29, 2014
Messages
78
Hi, recently when idling, my heater doesn't seem to blow warm air, but when I'm driving it immediately starts to blow warm. Any thoughts?

Thank you!
 
What does it blow when idling:
No air
Cool air
Luke warm air?

Then when you start driving:
Air temp warms up and/or air velocity picks up??
 
Any work done on coolant system? Check level and for air pocket.

OR could be temp blend door

Once engine is hot then heater core is hot and heat is there all the time.

Now if low on coolant then maybe at idle you are not getting any more hot coolant into heater core
Same if you have air pocket.

OR temp blend door is closing off heat at idle.

DO you have dual front temp control thingy?

IS it the same on both sides?
What about rear heat under seats?
 
Any work done on coolant system? Check level and for air pocket.

OR could be temp blend door

Once engine is hot then heater core is hot and heat is there all the time.

Now if low on coolant then maybe at idle you are not getting any more hot coolant into heater core
Same if you have air pocket.

OR temp blend door is closing off heat at idle.

DO you have dual front temp control thingy?

IS it the same on both sides?
What about rear heat under seats?
Thanks so much! I haven't had any work done recently. I do have the dual front temp control thingy 😃 . Yes same on both sides, I haven't checked under the seats yet.
 
yeah check under front seats in the rear I believe a little duct blows out air based on driver setting
 
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