Calling the Tech Pro's
Thread Starter
Safety Car
Joined: Dec 2000
Posts: 4,166
Likes: 14
From: Orlando Fl
Calling the Tech Pro's
Are the dampers that control which vent the AC and heat flow through controlled by a fuse and if so, which one? All air (heat or A/C) is only coming thru the Defrost vent and nothing seems to change that. Is it a suction tube? I disconnected the battery for a bit hoping to reset it, but no luck. (I'd even do it manually if i could for now) ....
Thread Starter
Safety Car
Joined: Dec 2000
Posts: 4,166
Likes: 14
From: Orlando Fl
Originally Posted by dpd
check the vacuum line under the battery tray that comes from the intake manifold.the ducts are controlled by vacuum while the blend doors are stepper motors.
Thread Starter
Safety Car
Joined: Dec 2000
Posts: 4,166
Likes: 14
From: Orlando Fl
Originally Posted by dpd
have you checked for faults?have you experienced the leaky battery syndrome?
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Ahhh, been here fixed this!! When my 98 was just out of warranty, this happened to me! Here is what causes it!
On back of the intake manifold there is a fitting. It houses the MAP sensor and supplies vacuum to the brake booster and vacuum to the HVAC system. Without vacuum the HVAC dampers fail in the defrost mode to allow you to see.
Here is a pic of the fitting:
Here is a picture of the rubber connection that fits on that manifold fitting.
Here is a picture of the vacuum resivour that is located in the passengers fender well. The lines connect to the bottom of the black plastic can.
Bill C
On back of the intake manifold there is a fitting. It houses the MAP sensor and supplies vacuum to the brake booster and vacuum to the HVAC system. Without vacuum the HVAC dampers fail in the defrost mode to allow you to see.
Here is a pic of the fitting:
Here is a picture of the rubber connection that fits on that manifold fitting.
Here is a picture of the vacuum resivour that is located in the passengers fender well. The lines connect to the bottom of the black plastic can.
Bill C
Thread Starter
Safety Car
Joined: Dec 2000
Posts: 4,166
Likes: 14
From: Orlando Fl
Originally Posted by Bill Curlee
Ahhh, been here fixed this!! When my 98 was just out of warranty, this happened to me! Here is what causes it!
On back of the intake manifold there is a fitting. It houses the MAP sensor and supplies vacuum to the brake booster and vacuum to the HVAC system. Without vacuum the HVAC dampers fail in the defrost mode to allow you to see.
Here is a pic of the fitting:
Here is a picture of the rubber connection that fits on that manifold fitting.
Here is a picture of the vacuum resivour that is located in the passengers fender well. The lines connect to the bottom of the black plastic can.
Bill C
On back of the intake manifold there is a fitting. It houses the MAP sensor and supplies vacuum to the brake booster and vacuum to the HVAC system. Without vacuum the HVAC dampers fail in the defrost mode to allow you to see.
Here is a pic of the fitting:
Here is a picture of the rubber connection that fits on that manifold fitting.
Here is a picture of the vacuum resivour that is located in the passengers fender well. The lines connect to the bottom of the black plastic can.
Bill C
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