Heater Gives Me a Headache...any ideas? :-(

My last car was a Buick Century. Near the end of it's life, if I ran the heater for a while I would get a minor headache. Well, it was old and nearly at the end of it's life, so I figured I would let it go until I bought a new car. Within 6 months the power steering broke and I bought my new car - a 2009 Toyota Prius with 15,000 miles on it.

I live in Minnesota.

Unfortunately, I've found that my Prius is even worse in this regard. It's like this -
1. Roll down the windows to air out the car then roll them up again (for all of the following)
2. Heater off, fan off - no problem, have driven a long time with no issues.
3. Heater on, recirculating air inside car - slightly headache after a while
4. Heater on, outside air coming in (usually on the thing that blows air on the windshield and keeps the windows from steaming up) - noticeable headache. Sometimes I notice within a few seconds, sometimes it takes a few minutes.

I was wondering if anyone had had the same problem and knew of any solutions. I've paid the dealership to check for exhaust leaks and they said there weren't any. I don't know what the person before me had, but I haven't had any air fresheners or carpet cleanet chemicals or anything in it since I bought it (almost a year ago).

I also had them replace the cabin air filter.

I've read about there being a mold problem in Prius's where people run the air conditioner all the time, but I don't do that - I live in Minnesota so I've hardly run the air conditioner at all. I'm not sure where the car is from, but I leave the car parked outside all winter - I would think any mold would have been cleared out by the subzero freezing temps in the winter. And while the car has a slightly "locker room" smell to it, it doesn't get any better or worse when I turn on the AC. And it's a 2009 model which supposedly has the new evaporator coil and such that Toyota thought would fix the problem.

This last weekend I rode in a relatives Mitsubishi Outlander for 3 hours and was reminded that not all cars give me a headache when I ride in them (though to be fair, we were running the AC not the heater.

Has anyone else had this problem? Has anyone heard of a solution?

Lol I think you need to ask your doctor, not us.

I'm sure the doctor, hearing that I get headaches in one car but not another, would advice me to buy a better car.

Really? You just said you got a headache in your Buick.

Hey man, you asked for ideas. I think your problem is health related, not Prius related. Get well champ.

I said they're worse in my Prius than in my Buick, which was old and falling apart.

Just drive with windows cracked with heat on while on your way to doctors

Definitely see a doctor...

...I already saw my doctor. He said "maybe you have allergies" after asking me if I smelled exhaust, and suggesting I get it checked for an exhaust leak.

Try switching to a charcoal/carbon cabin filter it will help with any allergies or fumes you may be encountering.Not that expensive and may help dramatically.

I would add a portable humidifier in your car, as well as a portable air purifier. The hot dry air is probably what's giving you headaches.

Would have you any specific suggestions on where to get one? I imagine the dealer doesn't sell them?

This the ebay link where I get mine from.My daughter has allergies and this helped on long trips.

http://shop.ebay.com/i.html?_from=R...ius charcoal filter&_sacat=See-All-Categories

Sounds like you are describing the defrost setting.

I see why you would think that, but in actuality you are. Most (all?) cars run the compressor in defrost mode. This is the same compressor that runs when the AC is cooling down the car. It runs in defrost mode so that the air will be dehumidified and won't add more fog to the windshield as the air blows on it.

The mold thing happens because the water that gets removed from the air can end up trapped in the system and the dampness can promote mold growth.

I would treat the car as if the AC was on all the time and do whatever people recommend doing when the car gets a bit of mold or mildew.

A filters treated with carbon and baking soda couldn't hurt either. I use this one:
Amazon.com: FRAM CF9846A Fresh Breeze Cabin Air Filter for select Mazda/ Mitsubishi/ Toyota models: Automotive

I pm'ed you.

I had a funky smell in my old 94 Saab 9000 Turbo. I attribute it to its previous owners leaving it for years somewhere in a very wooded area because you could smell it whenever you turned on the a/c or even just vent.

My solution was to run those febreze clip on vent air fresheners, and more importantly a de-fungiciding (if thats even a word lol) of the HVAC system with Ozium.

I bought a can of Ozium. Started up car, put a/c on high full cold blast and walked to the front of the car. Lifted Hood and went to the intake ducts in front of the wipers. This is where all of your fresh air comes into HVAC system when the fresh air mode is turned on (as opposed to recirculation mode)

Spray ozium in there liberally for 20-30seconds. Go back into cabin of car and smell air observing concentration levels of ozium sprayed. If you feel the air has changed enough to your liking smell wise, let the system continue to run for another minute.

I can guarantee most of your mold if any will be gone and any smell will be as well. You can re-treat monthly, or whenever you feel any smell coming back.

I have developed bad allergies over the years and have had bouts with headaches driving before. For me sunglasses (I am VERY fair skinned) on sunny days and a good smelling HVAC system has done wonders

As always YMMV

^^ that's good to know. I think that may be an excellent first step for the OP to try.

My allergies have kicked my @$$ this year (including a bout of bronchitis from it all). At home, I use at a minimum a MERV 11 HVAC filter, and I have a UV & Ozone light system on my duct work.

The OP's description of the problem is puzzling. If the problem came from mold or irritating chemicals in the system it should be worse during recirculation, but he states that outside air exacerbates the problem. This suggests that the real issue is outside of the car. Perhaps he has an allergy to something along his normal commute, but not experienced when riding in his friend's car.

The duct work used for outside air is unlikely to harbor anything nasty, but it is the only part of the heating system not used during recirculation.

The alternative is that the headaches are psychosomatic. It would take a blind test to eliminate this possibility.

Tom

Maybe the OP should remove the windshield wiper arms and the two-piece black plastic cover over the cowl, so that he can look into the cowl tray and see if there is anything unusual on it, like a dead rodent or a clogged drain which has allowed the growth of something nasty.