AC blows cold air through defrost vents.Many car drivers notice this problems.
Basically this problems are related to cracked vacuum line or loose vacuum line or loose worn out vacuum line hoses.
Inspecting it properly helps to confirm the problem.
If it will only blow through the defrost vents, then its a vacuum issue, as the vent selection is vacuum controlled.
But if you were only getting hot air, or cold air, but could get it out of any vents, then that would be the blend door.
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Basically this problems are related to cracked vacuum line or loose vacuum line or loose worn out vacuum line hoses.
Inspecting it properly helps to confirm the problem.
If it will only blow through the defrost vents, then its a vacuum issue, as the vent selection is vacuum controlled.
But if you were only getting hot air, or cold air, but could get it out of any vents, then that would be the blend door.
But as per your problem described,your problem is vacuum-related. The floor-heat-vent-defrost selection is vacuum-controlled, and in the absence of vacuum from the engine, the heat-A/C control doors revert to the "Defrost" mode as a safety issue. Look at all your vacuum lines, particularly those on the vacuum reserve canister under the fender.
The vacuum line gets overheated and melted in some cases,some times lines gets cracked or loose .
There are two red vacuum lines behind the upper manifold inspect both line properly.This basic details will help you thanks.
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