Mildew smell in the air vents? -
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Unread 09-27-2012, 07:28 PM   #1
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1997 ZJ 
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Mildew smell in the air vents?

I recently got my Jeep back from my ex, and today I drove it for the first time... I noticed when the air vents are on you can smell a mildew smell coming in the air... if you turn on the ac, then the smell goes away. Is this something that needs cleaned or is this a bigger problem?

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Unread 09-27-2012, 08:57 PM   #2
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its mold...they sell stuff at auto parts stores or online to kill 2-3 of these vids just to be sure these guys (other vids on the side pane) all cover it right...also check the instructions on the bottle....
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Unread 09-27-2012, 08:59 PM   #3
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Lysol also works, if you can stand the scent.
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Unread 09-29-2012, 10:46 PM   #4
Old, and in the way.
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Atmosclear works well, you can get it at Ace Hardware.
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Unread 09-29-2012, 10:55 PM   #5
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Try to set high heat 3-5 min before you turn off the key. The heat will dry the air passages and kill the mold very quick.
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Unread 09-29-2012, 11:14 PM   #6
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The cause of the musty smell to begin with is water accumulating in the HVAC box and becoming stagnant. Most likely your AC drain line is clogged and here's a real good thread on drilling a 1/4" whole to fish a wire through the line. It can't be accessed from the outside of your ZJ because the hose drains into the frame. Great design, not!

I don't bother to use silicone on a rubber plug and a piece of duct tape works just fine over the hole with no leaks. I have to clean this line out 2-3 times a years since I live in the woods and the tree crap tends to go down in the grate below the outside of the windshield.

I've actually put a real small hook on the end of the wire and have pulled leaf stems through the hole from the inside.

Good luck.
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Unread 09-30-2012, 06:17 AM   #7
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You can access the drain end by cutting a small hole in the frame. A more complicated but more effective solution is to clean the evaporator. You'll have to pull the lower ash tray trim section and glove box to give you comfortable{kinda} work space. Remove the neg battery cable. Remove the blower assy. and resistor or atc fan control. With a small wet dry vac tape some 1/2 to 5/8 clear plastic hose on the end. Then get a $7 walmart lawn and garden sprayer. Put some coil cleaner in {a/c supply house has it, the non acid variety} it. Bend the wand slightly so it'll negotiate the opening where the blower was, and hose the evaporator coil down. As an alternative they sell foaming coil cleaner in a can at auto parts stores. You can feel around in the hole to give you an idea where the coil sits.

Let the stuff soak for 20 or so. Take a soft bristle brush or a cut off mans comb{the little black ones} and gently {GENTLY} brush the coil fins. Take the vac set up and run it all the places you can reach.NO jabbing,and dont rake the hose across the coil face, you just want to pull stuff out of the coil. Run the hose along the bottom of the coil at the drain pan also. Empty your sprayer and refill with hot water and spray the coil to rinse. Repeat until you aren't sucking anymore crud out the vac. You will need to cover your carpet to catch drips. Verify the drain is open by looking under the jeep. If not then the above mentioned procedures need to be done.

If you park around trees this needs to be done every couple years or so. You will be amazed at the difference in air flow. A dirty coil will lead to freeze ups,overcharging, water dripping where it shouldn't ect. While you are in there clean the blower wheel on the fan as well. Being a 97 this has probaly never been done and will give you a smell free properly operating system.
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Unread 09-30-2012, 07:40 AM   #8
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Originally Posted by coralman View Post
...While you are in there clean the blower wheel on the fan as well...
+1^ Crud builds up on the blower cage fins, then it's out of balance and rumbles.
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