Main IndexAuto Repair Home Search Posts SEARCH
POSTS
Who's Online WHO'S
ONLINE
Log in LOG
IN









2006 Jeep Liberty CRD-Inconsistent Air Flow from Vents


  Email This Post



tilljo
New User

Mar 21, 2012, 11:58 PM

Post #1 of 12 (3131 views)
Shortcut
  post locked   2006 Jeep Liberty CRD-Inconsistent Air Flow from Vents  

2006
Jeep Liberty CRD
2.8L 4cyl
92,000 Miles

My 2006 Jeep Liberty has problems with intermittent AC airflow. Sometimes I have the AC on with normal airflow and then at random times the air will almost stop flowing from the vents (The air often stays cold too). The odd thing is that I will still hear the air flowing inside the system, it just won't be coming out the vents anymore. It's like some door within the system closes randomly. When I redirect the air through the floor vents, or defrost etc, I notice that the slight airflow changes to those settings yet fails to come out the vents except for a slight amount. What could this be?


Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

Mar 22, 2012, 6:18 AM

Post #2 of 12 (3089 views)
Shortcut
  post locked   Re: 2006 Jeep Liberty CRD-Inconsistent Air Flow from Vents [In reply to]  

 The mode selection is done through a series of air doors that are operated by vacuum. When there is either a partial or total loss of vacuum, the system will default to either defrost or on some vehicles, heat. Acceleration can also have an effect on the doors for the same reason.

Look under the hood for a small black plastic hose coming through the firewall. Follow it to the vacuum source looking for any breaks, cracks or leaks. Also follow any other lines that branch off because they may go to a vacuum reservoir (storage tank) and a leak there will cause the same problem. Using a vacuum gauge to determine if you have full vacuum at any given point is the best way to find it. You can cut into the line anywhere and splice it back together with a piece of vacuum hose. Find the broken line, you found your problem.




~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Mar 22, 2012, 7:58 AM

Post #3 of 12 (3081 views)
Shortcut
  post locked   Re: 2006 Jeep Liberty CRD-Inconsistent Air Flow from Vents [In reply to]  

tilljo and HT - could this be evaporator icing? Is there any condensate dripping if any humidity at all?

T
_________________________________________
Long retired now


(This post was edited by Tom Greenleaf on Mar 22, 2012, 8:00 AM)


Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

Mar 22, 2012, 10:03 AM

Post #4 of 12 (3074 views)
Shortcut
  post locked   Re: 2006 Jeep Liberty CRD-Inconsistent Air Flow from Vents [In reply to]  

That's possible if it's not coming out anywhere at all. I was assuming it was coming out the defrost because most people don't notice that.

If shutting it off for 15 minutes resolves it, that would point in that direction.




~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



tilljo
New User

Mar 22, 2012, 11:23 AM

Post #5 of 12 (3062 views)
Shortcut
  post locked   Re: 2006 Jeep Liberty CRD-Inconsistent Air Flow from Vents [In reply to]  

Thanks, I will check for a vacuum leak. I believe the problem occurs both when I have it on AC and just regular vent, but I will look into that further. When it happened last, I put my hand over the defrost but didn't feel any air coming out there. The only air that leaks out when the problem occurs seems to come from the appropriate vent (floor, defrost, etc...)


tilljo
New User

Mar 22, 2012, 11:26 AM

Post #6 of 12 (3061 views)
Shortcut
  post locked   Re: 2006 Jeep Liberty CRD-Inconsistent Air Flow from Vents [In reply to]  

Tom, I haven't noticed any condensate dripping when it happens but will look for that the next time it occurs.


Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

Mar 22, 2012, 11:39 AM

Post #7 of 12 (3059 views)
Shortcut
  post locked   Re: 2006 Jeep Liberty CRD-Inconsistent Air Flow from Vents [In reply to]  

If it happens when the A/C is off, that eliminates freeze up.




~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Mar 22, 2012, 12:14 PM

Post #8 of 12 (3054 views)
Shortcut
  post locked   Re: 2006 Jeep Liberty CRD-Inconsistent Air Flow from Vents [In reply to]  

Was just a thought HT and possibility on a tired mind. My house has been killing me will crap preoccupying me. Do have a very good grip on MVAC = motor vehicle or mobile vs HVAC which I consider for buildings or stationary A/C and fall short there with a clue that's dangerous.

Have icing going on at home with just a test as it has been warm to near hot here so early and have to re-study weak knowledge of how to ascertain superheat properties w no known weight of a total proper charge dammit or it would be easy. Frosted return (low side line) is all I need to see and know that ain't right but blew cool but didn't leave it on for the feared iceberg it can make.

Newer very high SEER rating which was stupid as they don't last as long TMK now in an area with limited need but real for short spells if only to get the damn humidity down which this system is. HVAC isn't my whole and never was my trade and does have serious differences in approach.

5 ton system with long lines is total overkill (stupid engineers said I had to have that much) vs the orig 3.5 ton that was fine in the hottest of days but just ran all the time. Short season as you know up here in cold country but still can get well over 100F for short periods.

Back to the thread at hand. Evap leaks are common on those vehicles and when at just the right point of a low charge will frost up before quitting. Will blow cold then airflow reduced till it quits as we know. No condensate would be a clue as well as a huge puddle after shut down more than normal. Not an opinion but a fact that 134a systems are so sensitive to correct charge with little tolerance. DIYers will forever buy death kits w the gauge on can and destroy systems as we know. I think you can still Google "death kits" many articles written by me! Probably down to page 10,000 by now which is a pest to find.

Be it known that for most vehicle A/C systems (about 70%) the problem is low charge and a leak frequently a shaft seal. Oil would be spewn around clutch area near always.

Glad I'm retired for the most part but still check out stuff for folks in person and advise on approach to the fix or if the silly vacuum line usually easy for me to find and fix with a splice of plain rubber hose if needed but this vehicle by the read does change its air flow direction w just low flow. Guess in some areas debris is a common issue but that would stay constant......

Tom


tilljo
New User

Mar 22, 2012, 8:50 PM

Post #9 of 12 (3033 views)
Shortcut
  post locked   Re: 2006 Jeep Liberty CRD-Inconsistent Air Flow from Vents [In reply to]  

Thanks for your input Tom and HT! The more I think about it, the more I suspect it may be a problem related to evaporator freeze up. As I recall, I don't think this issue has ever happened when only had it on vent. When the airflow would cease, I would then turn the AC off and try just regular vent air but it would still not work for a while. Usually given enough time, the air would start flowing again. When the air came back on, sometimes the vents make a hissing noise and a white fog comes out of the vents. Does this sound consistent with evaporator freeze up? If so, what do I need to do to fix this?

Thanks again for your help!
Jon


Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

Mar 22, 2012, 9:22 PM

Post #10 of 12 (3028 views)
Shortcut
  post locked   Re: 2006 Jeep Liberty CRD-Inconsistent Air Flow from Vents [In reply to]  

Yep, all the symptoms match. Check the low pressure cycling switch on the accumulator.




~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



jeetzky
New User

Sep 15, 2012, 8:42 PM

Post #11 of 12 (2180 views)
Shortcut
  post locked   Re: 2006 Jeep Liberty CRD-Inconsistent Air Flow from Vents [In reply to]  

Content full of l;inks and deleted.


(This post was edited by Hammer Time on Sep 15, 2012, 9:07 PM)


Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

Sep 15, 2012, 9:09 PM

Post #12 of 12 (2168 views)
Shortcut
  post locked   Re: 2006 Jeep Liberty CRD-Inconsistent Air Flow from Vents [In reply to]  

Please do not respond to old questions. If you need help with something, start a new question of your own.




~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.





Advertising


  Email This Post
 
 






Latest Forum Post

I have a 2006 Nissan maxima 3.5 There is nothing wrong with it but I was wonde...


blower motor did not work i pulled it out and tested it it worked i put it back...


I will try and be as clear as I can. 1999 Fleetwood tioga (ford e350) I turn my ...


So I have a 1999 ford escort zx2 it has the 2.0 i4 doc engine with the 5 speed t...


Hope everyone is doing well. Now that work has slowed down I decided to take a l...


I have a 91 Chevy pick up with a 4.3l v6 and 180,000 miles everything is origina...


Feed Button






Automotive Forum Categories
AC Auto Repair
Auto Body Repair
Auto Insurance
Automotive Repair
Automotive Wiring
Automotive World
Brake Systems
Car Care Tips
Car Racing
Car Shows and Events
Car Stereo Repair
Car Troubleshooting
Engine and Car Noises
Engine Fault Codes
Engine Troubleshooting
Exhaust System Repair
Gasoline and Motor Oils
General Discussions
Motor Vehicle Inspection
Motorcycle ATV Repairs
Motorcycle Body Repair
Motorcycle Clutch Repair
Motorcycle Engine Repair
Motorcycle Repair
Motorcycle Seat Repair
Remote Control Cars
Steering and Suspension
The Bargin Bin
Traffic Ticket Help
Tricks of the Trade
Truck Repair
Truck Repair Advice
Truck Engine Repair
Truck Suspension Repair
Car Forum - Sitemap


Search for (options) Privacy