Ever since I purchased this car, the A/C has smelled. At first, I thought it smelled the way it did because this car was used to carry hay on a farm, I found traces of hay in the trunk, under the seats, battery storage, and compartments; eventually got rid of it all, but the smell didn't go away.

Over the years, I have bought A/C disinfectants and cleaners that are made specifically for this purpose. I would take the first disinfectant spray-can with its hose and attach it to the condensation tube near the right front wheel; then, inject the solution inside the tube that leads to the condenser, let it sit for 10-15 minutes and then let it drain out most of the dirt or mold inside. Next, I would go inside the car, take out the A/C air-filter and replace it, would use the second disinfectant spray-can with its long red extension tube to spray all the inside vents with the A/C turned-off and then spray the outside vents with the A/C on full blast. But, it would only work for three or four months and then the odor would gradually come back.

I happen to live in Northern California, where there is plenty of moisture most of the year and hot during the summer. When I am not using the commercial method, as described earlier, I use an alternative cheaper method which is straight Lysol into the intake vents with A/C full-on; then, turn off the A/C, go inside, open the filter box, clean the filter, then spray the filter, the box and the vents. 

Since I have chronic bronchitis, I have no choice but to constantly monitor the condition of my A/C to prevent from getting sick. I will admit, this is not the only Toyota that I have owned; previously, I had two Tercels, and they both had A/C issues too; but, not as bad as this.

When the problem started last summer (2012), I took the car to the dealer and paid for a new filter and A/C system "flush". This worked! WAIT... for one week. I took the car back to the dealer and this time they told me they did a more "intense flush" of the A/C system. This seem to work and then the weather turned cooler and there was no need for A/C. However, as soon as the warm weather returned and thus the need for A/C the foul is BACK. I took the car in again to the dealer and was told that will do a new "system flush" and install a "bigger" carbon filter that would take care of the smell. I was also advised not use the recirculate mode in the car since the problem maybe related to mold growing in the A/C lines. Of course there will be a significant charge as well.

I called Toyota and was told that there are no complaints from other Prius' owners regarding these problem. The representative "consulted" with their engineer and reported that indeed there are no problems with the system and again advised that I only use the fresh air mode and NEVER the recirculate mode.

I am just frustrated. I feel that there must be other Toyota owners out there with the same/similar problem.

Does anybody have any recommendations for me?

Thanks.