Help! I have a Class C motorhome that's built on a Chevy Express 4500 chassis. Over the winter/spring mice went into the air intake for the cabin HVAC system by way of the cowl under the windshield. Needless to say it smells like mouse pee every time I turn on the heat or AC.

How do I gain access to the intake? Do I do it from the engine bay or do I tear the dashboard apart (how is that done?) and access it from that side? I couldn't find any cabin air filter so I'm assuming the Express either doesn't have one or is well hidden.

Any help/advice would be greatly appreciated!!

 

No, no cabin air filter. Access is from under the hood. I doubt the mice would have gotten past the heater core/AC evaporator.

Air enters through the cowl at the bottom of the windshield. The cowl cover comes off. From the cowl should be a duct that leads to the blower motor. This duct can be removed. The blower then forces the air through the A/C evaporator and then heater core. These are all within one housing. Getting into this housing may require disassembling part of the A/C system which is a big task. Otherwise you'd just have to spray a bunch of chemical in there.