Mode doors are set to default to the defrost position for safety reasons, clearing frost and fogging from windshield .
On most cars vacuum hoses from the engine power diaphragms that open and close the doors that change where the air blows in the heater system. Check for vacuum leaks. sometimes the diaphragms will go bad. It’s hard to say without actually digging into the system. There might even be something blocking the doors from moving that fell into your defrosters. But at least this gives you a few places to check
SOURCE: Air Conditioning Problem on a 92 GT mustang
Might be best to go for 60/2, sixty mph with 2 windows down! LOL Car is too old to be worried about little probs! Frankster016
SOURCE: 1998 Mustang - AC blows only through Defrost vents
You probably have a vacuum leak on the passenger side. its a small plastic hose some times they come unpluged from the engine. or brake.
SOURCE: defrost and floor wont blow air but vents work
these repairs are usually best left to an electromechanic but it can be doen by anyone with basic knowledge following the troubleshooting section in repair manual which can be purchase from local parts shop or online haynes or chiltons will do and get a multitester.
First check basics: are the fuses good to defrost blower? (fuse access refer to manual)
then see if there is power to the blower/defrost switch use multi meter at 20V setting
then see if there is power to blower unit under dash (see manual under interior section to access blower motor)
probe using same setting to test for power on each wire ( as you turn blower setting from low to high you shuld notice the voltagre climbs aswell)
if this checks out your blower motor is faulty replace and your good heres a few places to get the best deal on parts
ebay.com
Peach street autorecylcing 18003652341
www.godspeedmotorsportsonline.com
135 views
Usually answered in minutes!
I have even seen mouse nests block the doors
×