How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Dan Your Own Question
Dan, Technician
Category: Chevy
Satisfied Customers: 24432
Experience:  Independent Shop Experience, 2 Year Automotive Diploma, & Access to Information Database
Type Your Chevy Question Here...
Dan is online now
A new question is answered every 9 seconds

My 05 Tahoe blows cold air in the front until you rev it up,

This answer was rated:

My '05 Tahoe blows cold air in the front until you rev it up, even after the motor is warmed up and the rear heat only blows cold air.
Hello, my name is XXXXX XXXXX I'm here to help get your problem solved. This either means you have air in heater core or heater core is clogged. Air would only be in system if recent work was done. You can disconnect both hoses going to the heater core and use a garden hose to flush it out from both direction. The water pump turns as fast as the engine so when your moving the water pump is turning faster which forces coolant through clogged heater core which is why you have heat when moving. The flush would be about $150 to have done at a shop if it isn't something you want to do yourself. Let me know if there is anything else I can do to help. Thanks.
Customer: replied 3 years ago.

But, that still doesn't explain why my rear heat doesn't work at all


Did you have a component in cooling system replaced that may have let air into system? Did both stop working at the same time or different times? Thanks.
Customer: replied 3 years ago.

No, I haven't replaced any components in in my cooling system, and yes they both started giving me problems at the same time.



It sounds like the heater core is clogged which will cause restriction on flow to auxiliary heater core. If it was anything else such as blend doors you wouldn't have heat at all so I would still recommend flushing out the heater core which should take care of the problem. You can feel hoses going to heater core, if one is a lot hotter then the other this means it is not getting good flow through it. Let me know if there is anything else I can do to help or if you run into questions, thanks.

Dan and 8 other Chevy Specialists are ready to help you