HVAC system vents not functioning

althepa · 12-15-2012, 06:13 AM

Got a new problem with the 07 328i 4-door. The vents won't produce air on any setting. The fan is running and defroster works, but specifically, the vents facing the driver will not allow air to flow. Looks like flappers allowing flow out of the vents aren't engaging.

Air will blow onto the windshield from the defroster vents, and to the rear passengers from those vents.

Any quick fixes for this? I really am not relishing another $50 trip to the dealer under the CPO warranty.

Efthreeoh · 12-15-2012, 07:11 AM

There are 5 stepper motors in the system. Sounds like some are not working. I think the dealer needs to evaluate and do the repair. Good news is the dash does not have to come out to replace them.

lowcountrylife · 12-15-2012, 05:42 PM

I had the same problem a few months back. Apparently in the pre-lci models, the seal on the cowl cover is not as tight as it should be. There is a bolt on the top of the fan motor (passenger side of engine bay) which is subjected to water dripping on it from the cowl cover. There are 4 or 5 bolts holdong the cowl cover on. Take it off and spray some wd40 int the opening. I put my hand inside and made sure the lubricant got to the bolt head. Spin the fan blades several times to loosen and you should be fine. This has happened once since, after spray foaming my car and apparently allowing the soap to drip where it shouldn't. I attached a link which is where the original info was found.
Good Luck.
http://www.e90post.com/forums/showthread.php?t=542618

althepa · 12-16-2012, 05:30 PM

Quote:

Originally Posted by lowcountrylife

I had the same problem a few months back. Apparently in the pre-lci models, the seal on the cowl cover is not as tight as it should be. There is a bolt on the top of the fan motor (passenger side of engine bay) which is subjected to water dripping on it from the cowl cover. There are 4 or 5 bolts holdong the cowl cover on. Take it off and spray some wd40 int the opening. I put my hand inside and made sure the lubricant got to the bolt head. Spin the fan blades several times to loosen and you should be fine. This has happened once since, after spray foaming my car and apparently allowing the soap to drip where it shouldn't. I attached a link which is where the original info was found.
Good Luck.
http://www.e90post.com/forums/showthread.php?t=542618

Thanks for taking the time to respond. If I read this correctly, this would fix a non-running (seized) fan. My fan blows fine, but the internal flap valves for the vents aren't opening.

lowcountrylife · 12-16-2012, 06:18 PM

If there is nothing coming out of the vents when you have the center fan control on, this will take care of a "seized" fan. It is the corroded bolt at the top of the fan that is the problem. I have the same car and it took 5 minutes to fix. That particular motor (actually the particular bolt from the motor through the fan blades) is the one causing this, also the reason why your defrost still works. If your car is RT side steering, obviously the side of the engine bay will be opposite.

LittleBlue · 01-17-2013, 08:02 AM

Question: I did the same and took care of the squeek, my question now is the fresh air vents, it seems at times that they don't open to let the fresh air in automatically when the outside temps is above 40 degrees F, is there a minimumum outside temp that it needs to be at so the fresh air vents to operate normally without the A/C needing to be on? Otherwise it keeps getting hotter and hotter in the car and climate control set at 68 degrees F and the inside of the car could reach 80, any thoughts? are they sticking shut? Because when they do open I hear a flop as if the rubber flaps having trouble dissengaging from the vent walls, does that make sense? Anyone knows if this can be reached from the engine bay? when I turn the A/C on then everything works fine! but should I have to keep the A/C engaged and the compressor running even if the outside temps are at 40?

12-15-2012, 06:13 AM	#1
althepa New Member 1 Rep 15 Posts Drives: 07 328i 4-door Join Date: Jun 2009 Location: Chicago & Washington DC iTrader: (0)	HVAC system vents not functioning Got a new problem with the 07 328i 4-door. The vents won't produce air on any setting. The fan is running and defroster works, but specifically, the vents facing the driver will not allow air to flow. Looks like flappers allowing flow out of the vents aren't engaging. Air will blow onto the windshield from the defroster vents, and to the rear passengers from those vents. Any quick fixes for this? I really am not relishing another $50 trip to the dealer under the CPO warranty.
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12-15-2012, 07:11 AM	#2
Efthreeoh General 17278 Rep 18,722 Posts Drives: The E90 + Z4 Coupe & Z3 R'ster Join Date: May 2012 Location: Virginia iTrader: (0)	There are 5 stepper motors in the system. Sounds like some are not working. I think the dealer needs to evaluate and do the repair. Good news is the dash does not have to come out to replace them.
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12-15-2012, 05:42 PM	#3
lowcountrylife Registered 0 Rep 3 Posts Drives: Montego Blue e90 Join Date: May 2012 Location: Hilton Head Island iTrader: (0)	Try this first. I had the same problem a few months back. Apparently in the pre-lci models, the seal on the cowl cover is not as tight as it should be. There is a bolt on the top of the fan motor (passenger side of engine bay) which is subjected to water dripping on it from the cowl cover. There are 4 or 5 bolts holdong the cowl cover on. Take it off and spray some wd40 int the opening. I put my hand inside and made sure the lubricant got to the bolt head. Spin the fan blades several times to loosen and you should be fine. This has happened once since, after spray foaming my car and apparently allowing the soap to drip where it shouldn't. I attached a link which is where the original info was found. Good Luck. http://www.e90post.com/forums/showthread.php?t=542618
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12-16-2012, 06:18 PM	#5
lowcountrylife Registered 0 Rep 3 Posts Drives: Montego Blue e90 Join Date: May 2012 Location: Hilton Head Island iTrader: (0)	If there is nothing coming out of the vents when you have the center fan control on, this will take care of a "seized" fan. It is the corroded bolt at the top of the fan that is the problem. I have the same car and it took 5 minutes to fix. That particular motor (actually the particular bolt from the motor through the fan blades) is the one causing this, also the reason why your defrost still works. If your car is RT side steering, obviously the side of the engine bay will be opposite.
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01-17-2013, 08:02 AM	#6
LittleBlue Second Lieutenant 24 Rep 254 Posts Drives: 2022 G30 M Sport Join Date: Jul 2007 Location: U.S.A iTrader: (0) Garage List 2022 BMW 530I M Sport [0.00] [10.00]	Question: I did the same and took care of the squeek, my question now is the fresh air vents, it seems at times that they don't open to let the fresh air in automatically when the outside temps is above 40 degrees F, is there a minimumum outside temp that it needs to be at so the fresh air vents to operate normally without the A/C needing to be on? Otherwise it keeps getting hotter and hotter in the car and climate control set at 68 degrees F and the inside of the car could reach 80, any thoughts? are they sticking shut? Because when they do open I hear a flop as if the rubber flaps having trouble dissengaging from the vent walls, does that make sense? Anyone knows if this can be reached from the engine bay? when I turn the A/C on then everything works fine! but should I have to keep the A/C engaged and the compressor running even if the outside temps are at 40?
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