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98 STS Blend Doors?

6718 Views 16 Replies 6 Participants Last post by  MoistCabbage
I have had the STS about 9 months now and having gone through summer/winter season, I think I may have blend door issues.

In the winter, the heat is working, but the car is still cold.
In the summer, the air is working, but the car is still hot.

I believe from the blend doors not closing completely and letting outside air into the cabin. Gets a little better on Recirculate, but still not blocking the outside air.

Where are the blend doors on a 98 STS? No codes.

Robert D
1 - 6 of 17 Posts
Ranger, No codes.

Sub, the cabin temp sensor is to the left of the steering column. I'll have to remove the glove box tomorrow.
Spent all day doing brakes on my F250 today.

Like I said, Heat/AC working properly, except for outside air coming in.

Am I even headed in the right direction with diagnosing the blend doors?
Or is it something else I need to look at to stop the outside air?

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Sub, yes. I have been using Recirc to make it better, but still getting external air into the cabin. The reason I want to stop external air is because there is so much of it, the cabin does not get comfortably warm or cool, depending on the season. Winter, feet are freezing. Summer, almost at the point of sweating all the time.
Put your hand in front of the vents, feels great. Exact opposite on the feet. I dont have any pc canned air. Would an air compressor be too much?

Ranger, ambient air temp is correct on the dash.

Guys, I really appreciate you trying to help. Hopefully I am telling you everything .. I really am trying.
Thanks guys, I will try all of this in the morning. I finally got the brakes complete on the F250.
Will post tomorrow with the results.
OK, the sensors fan is running. I do hear it. I blew out the sensor, which really was not that dirty. But I guess any dirt is bad.
Unfortunatey, my wife has driver the car every day and I have not had a chance to check it.
I would still like to remove the sensor fan and clean/oil it.

Reading back thru this post, sub mentioned the rear diverter. The rear works great. I also still need to pull the glove box out and see what I have there too.
Thanks everyone ... I blew out the sensor and oiled the fan and all is well.
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