why does the a/c stop blowing thru the front vents and comming thru tha defrost vents

Asked by Jul 21, 2013 at 05:45 PM about the 2001 Dodge Ram 1500 4 Dr SLT 4WD Quad Cab SB

Question type: Maintenance & Repair

When I accelerate wwith the air on it stops blowing thru thefront vents and sterat blowing
thru the defrost and when you let off the accelerator the the air starts blowing thru the
front vents like it should.  Please help. Thanks.

5 Answers

120,945

Could be a vacuum issue. Some air diverters in the duct work are vacuum controlled. Not sure if yours is but if it is that's where I would look first.

4 people found this helpful.
120,945

Yes vacuum is supplied to the air control assembly by tubing to the intake manifold. Inspect the vacuum line for leaks and cracks. There is also a check valve in that line. (Note direction of check valve before removing it for testing) Apply 8 inches of vacuum, with hand-held vacuum pump, to engine side of check valve. You should be able to pull air thru the valve. Apply vacuum to air control side of check valve. The valve should hold vacuum. If not replace the check valve.

2 people found this helpful.
120,945

Check valve is connected to intake manifold with black vacuum supply line.

3 people found this helpful.
20

I have a 1997 Ram 1500 and dandyoun is 100% correct. My face vents would blow until about 1/3 throttle and then they would shut off until I backed off of the gas pedal. My check valve was located on the passenger side with a 90° elbow that connected it to the intake manifold just to the rear of the pcv hose nipple. I could blow air through it in both directions so I cleaned it with Brakeclean and it is working perfectly again. Problem solved. Thanks dandyoun!

2 people found this helpful.

it's probably the vacuum line going into to the cruise control servo. it's located under the battery. mine was doing the same thing. i looked at the vacuum line going into cruise control servo and it visually looked good. when i grabbed it ...it fell off in my hand. removed broken end and reinserted the vacuum line into the rubber elbow and bingo... it fixed my a/c problem and my cruise problem. hope this helps

Your Answer

Ram 1500

Looking for a Used Ram 1500 in your area?

CarGurus has 9,549 nationwide Ram 1500 listings starting at $800.

ZIP:

Dodge Ram 1500 Experts

  • #1
    Dan Connell
    Reputation
    6,950
  • #2
    pudgybear
    Reputation
    6,620
  • #3
    dandyoun
    Reputation
    6,170
View All

Related Models For Sale

Used Ford F-150
2,344 Great Deals out of 215,478 listings starting at $1,300
Used Chevrolet Silverado 1500
1,781 Great Deals out of 149,289 listings starting at $1,495
Used Dodge Ram 2500
147 Great Deals out of 4,934 listings starting at $2,495
Used GMC Sierra 1500
722 Great Deals out of 58,462 listings starting at $1,900
Used Toyota Tundra
478 Great Deals out of 38,526 listings starting at $1,999
Used Toyota Tacoma
439 Great Deals out of 44,078 listings starting at $1,995
Used Ford F-250 Super Duty
374 Great Deals out of 42,218 listings starting at $1,600
Used Dodge Dakota
68 Great Deals out of 3,085 listings starting at $1,800
Used Ford Mustang
270 Great Deals out of 37,084 listings starting at $2,150
Used Dodge Ram 3500
74 Great Deals out of 2,162 listings starting at $5,980

Used Cars For Sale

2010 Dodge Ram 1500 For Sale
49 Great Deals out of 1,218 listings starting at $4,800
2009 Dodge Ram 1500 For Sale
47 Great Deals out of 963 listings starting at $4,500
2008 Dodge Ram 1500 For Sale
67 Great Deals out of 1,402 listings starting at $3,995
2007 Dodge Ram 1500 For Sale
39 Great Deals out of 1,307 listings starting at $3,999
2006 Dodge Ram 1500 For Sale
37 Great Deals out of 1,030 listings starting at $2,950

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use.