Help for a stinky heater

Dear Tom and Ray: I have a problem. I recently bought a 1992 Subaru Loyale. I hope it will be the best $400 car I ever bought, but there is one small problem. The heat stinks! The smell is an alluring combination of cat pee, ammonia, rotting dead animal, dirty socks and the smell you could expect about three or four hours after the church bean supper. OK, you get the idea. As an avid fan of yours, I would think that you guys have answers for me. Being a car-repair-savvy person, I started taking out the dash in the car, searching for the mouse and squirrel keg party gone wrong. After getting the dash about halfway out, the pile of screws and panels was higher than the dash itself. I got scared and put it back together. So, here I am after three hours of work, with no solution. What do I do?

Gabe

Tom: There are several possibilities, Gabe. The one you should pray for is a plugged-up evaporator drain. When the air conditioner removes moisture from the passenger compartment, that moisture is supposed to drip out under the car through the evaporator drain.

Ray: That drain can easily get plugged up with debris, creating your very own Environmental Protection Agency superfund site in the ductwork. So, start by asking someone to blow out the evaporator drain with compressed air and treat the ducts with some mold-killing spray, and hope that solves your problem.

Tom: When it doesn't, you're going to be forced to conclude that what's causing your smell is a dead and decomposing mouse.

Ray: I'll even tell you where it is. It's in the box that surrounds the heater core. So you were right to start taking apart the dashboard to get to it.

Tom: But, having looked at the repair manual for the '92 Loyale, you were right to stop, too. You weren't exaggerating when you said your parts pile was higher than the dash. It's about a thousand-step process. I don't blame you for leaving that as a last resort.

Ray: Although it can take months, the mouse will eventually decompose completely. You can hasten that process, and make it more bearable, by emptying a can of Lysol in there. To do it, turn on the engine, put the heat and fan on "high," open all of the windows and spray the deodorizer into the fresh-air intake at the cowl, outside the car where the hood meets the windshield. Then let it work its way through the vents for a while. It should help.

But just as importantly, you need to prevent future mice from seeking warmth in your heating ducts. You need to either park in a garage, use a secure car cover or put some sort of screening inside the cowl to prevent mice from climbing into your heater.