Strange ac/ventilation issue
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Joined: Oct 2011
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From: A to the Z (the state)
'06 E55
Strange ac/ventilation issue
Heres the deal: recently my ac has been kinda weak. I noticed that the drivers side blew warmer air than the passenger side when both were put on the lowest temp. I had the system recharged and now both sides are blowing somewhat cool when the temp is high outside. It still has problems cooling down the inside of the car when it's been out in the hot sun. If it is in the evening, I can freeze myself out.
The strange thing is the volume of air flow and what happens on the highway. The longer I drive on the highway, the weaker the airflow gets. I can have the fan on high and I can clearly hear the blower going at full tilt, but the air barely trickles out. I've closed off all the vents and cycled through all of the different modes with no luck. If I stop the car and turn it off, when I get back in, the airflow is back to normal, which isn't all that spectacular. Back on the highway and it decreases enough to have me sweating. I've tried varying the rpm, doing a pull, and even putting in neutral for a bit. Nothing works.
One strange thing happened this weekend. I was driving to Houston, got stuck in traffic, and the ac started kicking butt like it should. It was 100 degrees outside and I was cold. This did not last.
Are these vents somehow vacuum actuated or what? Any ideas?
The strange thing is the volume of air flow and what happens on the highway. The longer I drive on the highway, the weaker the airflow gets. I can have the fan on high and I can clearly hear the blower going at full tilt, but the air barely trickles out. I've closed off all the vents and cycled through all of the different modes with no luck. If I stop the car and turn it off, when I get back in, the airflow is back to normal, which isn't all that spectacular. Back on the highway and it decreases enough to have me sweating. I've tried varying the rpm, doing a pull, and even putting in neutral for a bit. Nothing works.
One strange thing happened this weekend. I was driving to Houston, got stuck in traffic, and the ac started kicking butt like it should. It was 100 degrees outside and I was cold. This did not last.
Are these vents somehow vacuum actuated or what? Any ideas?
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Joined: Mar 2011
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From: The Granite State
.
Next time it acts weird reach back and check the vents in the center console that blow into the rear seat area....
I had an issue once where the front A/C was running full-blast for over an hour and I couldn't seem to get to a comfortable temperature. By coincidence I felt those rear vents and they were belching HOT air into the car. Basically there was an HVAC "Battle Royale" going on between hot and cold....and hot was winning.
There is apparently a valve that can stick and prevent the rear AC from doing the same thing as the front AC. It can occasionally "fix" itself which may explain why the issue seems intermittent. Sorry I don't recall more of the details, but I do remember reading a thread about it here somewhere and I don't recall the fix being all that expensive.
-G
I had an issue once where the front A/C was running full-blast for over an hour and I couldn't seem to get to a comfortable temperature. By coincidence I felt those rear vents and they were belching HOT air into the car. Basically there was an HVAC "Battle Royale" going on between hot and cold....and hot was winning.
There is apparently a valve that can stick and prevent the rear AC from doing the same thing as the front AC. It can occasionally "fix" itself which may explain why the issue seems intermittent. Sorry I don't recall more of the details, but I do remember reading a thread about it here somewhere and I don't recall the fix being all that expensive.
-G
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From: A to the Z (the state)
'06 E55
The rear vents are blowing about like the fronts do. I have them all set to low setting.
I didn't even think about something freezing over, but it could happen. All this humid air in the south makes for lots of condensation on the cold parts.
I didn't even think about something freezing over, but it could happen. All this humid air in the south makes for lots of condensation on the cold parts.
Super Member
Joined: Sep 2010
Posts: 529
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From: Wherever isn't gonna get me hit
'05 SL65, '13 FX4 Eco
I had a bunch of problems with my AC as well. When I was just sitting in traffic I could have had it all the way on Low and blasting as hard as it could and it would just be kinda cold. My rear vents would blow hot air no matter what. Always thought the AC system was a bit weak in these cars.
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Joined: Mar 2011
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From: Orange County, CA.
one car at a time
There is apparently a valve that can stick and prevent the rear AC from doing the same thing as the front AC. It can occasionally "fix" itself which may explain why the issue seems intermittent. Sorry I don't recall more of the details, but I do remember reading a thread about it here somewhere and I don't recall the fix being all that expensive.
-G
-G
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Joined: Mar 2010
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From: San Diego
F-250
The issue with hot air to rear seats is a bad Heater control valve. There is a wrire up (DIY) here somewhere. Just grabed the parts out of my stock closet A 211 832 05 84.
The problem you have Denroll sounds like some flaky actuators. There are 5 or 6 that each control a different zone.
Here is one being addressed
The problem you have Denroll sounds like some flaky actuators. There are 5 or 6 that each control a different zone.
Here is one being addressed
