Smelly Sienna

njanja Member Posts: 8
edited July 2014 in Toyota
Hello All,

I have a 2004 Toyota Sienna XLE. Bought it used at 60K miles in Aug 09.

After 1 month since I bought it, van started smelling like mold. First I thought dealer was messing with it (I had given for cleaning after buying the van). However smell was getting worse. Gave it to another dealer to get rid of the smell. They did something to reduce the smell significantly(used some kind of charcol canister to absord the smell). During winter smell reduced almost to nothing.

Then we took the van to Florida where it was warmer and the smell got much stronger. Now, its getting warmer here and smell seems to be coming back.

Has anyone seen this type of problem? It seems to come back when the weather gets warmer and disappears when the AC is truned on at 70. When the AC turned off, smell comes back.

Please let me know how to get rid of it.



  • wwestwwest Member Posts: 10,706
    Install an EED kit from
  • ateixeiraateixeira Member Posts: 72,587
    I keep a box of baking soda in there.

    The kids eat in the back and spills are inevitable. I like having at least something in there to absorb any odors.
  • wwestwwest Member Posts: 10,706
    If you park under shelter then religiously lowering the windows slightly each and every time will allow the condensate to evaporate and "flow" out of the cabin more readily.
  • njanja Member Posts: 8
    Thanks for the replies. Is there any particular kit which you can recommend? Basically it will mask the smell. right?
  • wwestwwest Member Posts: 10,706
    "..mask the smell..."

    No, the EED, Electronic Evaporator Dryer, will intermittently run the system blower for brief/short periods for some time after the ignition is switched off. That's in order to disperse the thin film of condensate previously accumulated on the evaporator vane surface area.

    It's that moisture, if it remains concentrated within the HVAC plenum area, that helps to provide a perfect breeding environment for the microbes, "BUGS", whose "leavings" result in that dirty gym socks, mold and mildew, odor.
  • julzs71julzs71 Member Posts: 1
    I had the same exact thing happen. I took it in and complained about it. They said nothing was wrong with it. It smelled like dirty feet. It happened also on hotter days it would smell worse. It also had a diesel truck sound when going up hills or inclines. Anyway, it turned out to be 3 catalytic convertors. Ours needed to be replaced the day we bought it (4yrs ago) and then I just had them replaced again 2 months ago. See if that is it. The check engine light didn't go off for 3 years. Then two months ago it finally did.
  • njanja Member Posts: 8
    Thanks for the reply.

    Dealer told me its not catalytic converter! But I am not sure whether they checked it or not. I will ask them to check it out.
  • wwestwwest Member Posts: 10,706
    Sounds as if you had two separate problems/symptoms. Burned vanish or sulphur smell is generally the catalytic converter. Dirty feet smell is generally the result of mold and mildew buildup/accumulation within the HVAC plenum area containing the cooling evaporator.
  • njanja Member Posts: 8
    Smell( sulphur/dirty feet) :

    * builds up when the van is not used/parked and
    * reduces when the heater is turned up to 70. When I switch on the AC slight smell sneaks in again.

    If its Catalytic converter : How do I make sure that its the one causing it?

    If its HVAC : what exactly needs to be done in this case? replace it or clean it? Should I get it done at the dealer or any other recommendation?

  • wwestwwest Member Posts: 10,706
    "..dirty feet smell.."

    If you park under cover then simply, but religiously, lower the windows slightly each and every night.
  • njanja Member Posts: 8
    >> If you park under cover then simply, but religiously, lower the windows slightly each and every night.

    I dont have that luxury now. Even if that is the case, how long should I be doing it? Couple of weeks?
  • wwestwwest Member Posts: 10,706
    For as long as you make use of the A/C on a daily basis.

    My '01 F/awd RX300 has a c-best option, two actually, that I had the dealer set so that I could disable the A/C compressor indefinitely throughout the winter months. The second one unlinks the A/C from operating automatically in defrost/defog/demist mode.

    As long as the A/C doesn't operate there is no condensate build up in the A/C plenum and thus no odor. And as a "special" side benefit no instances of sudden windshield fogging during cool or cold weather operation.
  • maxwell10maxwell10 Member Posts: 29
    i had the same problem with my chevy truck when new.

    its water not being dried off the ac condensor. they had to install a odor kit dry off unit on my ac condensor,

    the kit turns the ac fan motor on high for about 15 sec every hour/ 24 hrs per day.

    but the fan does dry off the condensor and stopped the odor.

    you must find a way to dry off the condensor,

    you may have to turn the blower on high yourself each time you drive and let it run for at least 1 or 2 mins.

    on my truck the odor started in the springtime.

    good luck, no sprays or baking soda ever stopped the odor, you must dry off the condenser.

    good luck,
  • wwestwwest Member Posts: 10,706
    edited March 2010
    You mean to say evaporator, the condensor is the A/C component mounted forward of the engine cooling radiator. The kit they used was likely the EED from and only runs for 15 seconds intermittently for the first hour after the ignition is switched off.
  • maxwell10maxwell10 Member Posts: 29

    am sure your are right it is the evaporator, part of the ac unit that is inside the dash.

    The GM kit they installed is called a Odor Kit: I got a copy of the tech bulletin for the unit. It was installed in 2000 and still works fine.

    It operates the fan on high speed for about 15 seconds each hr 24/7. Now that I am retired and do not drive the truck daily, the unit will run the battery down in the winter.

    But that fan blowing across the evaporator, drying it off, has eliminated the odor problem.

    My GM service tech said they had installed about 7 of these units on pickups at the local dealership. Not something GM is proud of I guess.
  • njanja Member Posts: 8
    Visited a dealer today. He recommended cleaning the AC evaporator with some kind of foam. Seems they do that in these cases. Will update once its done.
  • wwestwwest Member Posts: 10,706
    Temporary fix, work.

    Be sure and read the label or the MSDS fact sheet on the fungicidal foam as you'll be breathing that into your lungs for quite some time to come.
  • njanja Member Posts: 8
    so, the only way out of this is to install the kit?

    btw, how much do these kits cost? cant find any pricing on the sellers site.
    and does the dashboard have to be open to install one of these? can it be done anywhere else ( read cheaper) or by myself?

  • njanja Member Posts: 8
    Well, it didn't go well. Van still smells moldy :(

    What do I do next? How do I make sure that its not coming from catalytic converter? How to check for it?

    If it was evaporator, it should have at least reduced the moldy smell. Correct?
  • maxwell10maxwell10 Member Posts: 29

    does the odor smell like wet clothes mama left in the basket for a few days.
    that was the smell in my 2000 model chevy truck and the fan blowing across the evaporator every hr solved the smell problem.

    we purchased a new house AC/Heat pump unit 2 years ago, it is twice as big as the one taken out. The new unit has twice as many cooling fins and they are closly packed together,

    each spring during AC startup it has a odor problem, the company gave me some type spray material that I have to spray on to the cooling fins to kill the odor. Same type problem, AC dealer said these new high eff units are all having the same odor problem, its moisture and until they are run a while they have to have a shot of chemical.

    good luck with the problem.
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