AC colder on one side of car?
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Joined: Apr 2013
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From: Gainesville, FL: In a garage or in a bar, or a garage with a bar in it.
2005 E55, 2011 Honda Push Mower (21 inch deck bishes)
AC colder on one side of car?
Hot as satan's sack today so cranked both the left and right side to LO and Max Cool. Both settings on the location dial were the same, but the passenger side center vent was noticeably cooler than the driver's center and driver door. Maybe a stuck vacuum actuator on the blend door, or a dying thermocouple on that side? I wouldn't mind if I had a right hand drive model 
Anyone else ever experienced this?
Anyone else ever experienced this?
Last edited by typhoon43; Jul 10, 2013 at 10:44 PM.
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From: Sleepy Hollow, IL
65 Chevelle Wagon w/ C5 frame, 08 ML63, 04 S600, 04 E55,(sold) 00 ML55,(sold) 98 C43-55K Swap
Sounds like its low on charge. Evaporator is closer to the passenger side and by the time the cool air gets all the way to the drivers side it warms up. The AC system usally will hiss when turning on and off if its low on charge. If you hear this as well, its a safe bet you need a AC charge.
Thread Starter
Senior Member
Joined: Apr 2013
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From: Gainesville, FL: In a garage or in a bar, or a garage with a bar in it.
2005 E55, 2011 Honda Push Mower (21 inch deck bishes)
Awesome guys. I'm making a small list of things to have an Indy check out since I've only had the car for a few months, and want some changes made in STAR. I'm assuming these cars are a little more complicated than me plugging in a Pep Boys "Cool in a Can" setup and squeezing some R-134 in.
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Joined: Jan 2007
Posts: 852
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From: Sleepy Hollow, IL
65 Chevelle Wagon w/ C5 frame, 08 ML63, 04 S600, 04 E55,(sold) 00 ML55,(sold) 98 C43-55K Swap
Awesome guys. I'm making a small list of things to have an Indy check out since I've only had the car for a few months, and want some changes made in STAR. I'm assuming these cars are a little more complicated than me plugging in a Pep Boys "Cool in a Can" setup and squeezing some R-134 in.
If you do add a can make sure it's plain r134. No oil or leak fix etc. I would say for the $10 why not. At the very least you'll be cool untill your Indy looks at it. If you want it perfect though you need a set of proper AC gauges and leak detection dye would be a good idea.
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Joined: Apr 2013
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From: New Orleans
2003 E55
Sounds like a duo valve to me. Fairly common occurrence on the 211's. Typically if it was low on refrigerant, it wouldn't blow as cold, but still the same temperature throughout the car. The refrigerant has no way of dictating where it is going in the system, or which vents will blow colder than the others.
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AMG E55
Either way, I'll be keeping an eye on this thread and will update all with any options I try.
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Junior Member
Joined: Apr 2013
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From: New Orleans
2003 E55
The duo valve is located beneath the wiper cowl. Not hard to change out. If you wanted to test it first, you could gain access to the duo valve, and tap it with a small hammer to try and release the valves on the inside. This wont always work, but if it does then its an easy way to diagnose the problem. I would be willing to bet that its the duo valve though, given the symptoms you exhibit, as well as my time working with mercedes benz and seeing this problem numerous times, most prominently on 211's.
Also, keep in mind that if the refrigerant level is ok, and you just start arbitrarily adding refrigerant you could cause damage to the system.
Also, keep in mind that if the refrigerant level is ok, and you just start arbitrarily adding refrigerant you could cause damage to the system.
Last edited by 211.076; Jul 12, 2013 at 10:36 PM.
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From: Orange County, CA.
one car at a time
211.076 appears to have the logical answer on this one...
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From: Washington
10 E63, Sold -07 E63
Doubt its freon. Do you have the same amount of air blowing on each vent? Low on freon would mean you have a leak since our AC is a closed system. Also if you have cold air in one vent, it would not warm up that quick that it would be warm enough on the other vent. My guess is a blending valve or an actuator.
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w211 / 2005 ,E 36 325i tunned /1995
I have the same problem on my w211 220cdi ! the air blow is the same on the both side,but in the left side is not so cold like in the right side ! what is the problem: Freon ? Duo valve ? Actuator (what is this?) Thanks in advance!
