A brief write up about my weekend project to install a cabin air filter in my Fiero.

Background:
For the past few years California has been under yearly fires in my county. Air quality gets bad and while commuting to work I was noticeably affected. This week I noticed the sweet smell of coolant descending into my cabin when the heater was on, so I knew it was time to replace the good old heater core. While working in that vicinity, I got to thinking, why not add a cabin air filter? After all, a few years go I removed my AC components giving me ample space in the HVAC box.

Project goals:
1. Use an affordable, off the shelf cabin filter that is readily available.
2. Make replacement, quick and easy.
3. Save space and remove unneeded items for a cleaner front compartment while keeping a stockish look.
4. Provide a better way to keep debris away from the infamous blower resistor.

Execution:
1. After looking over the space and deciding an ideal filter placement I took measurements for a range of suitable filters.
7.5-8" wide
6.5-7.2" tall
1-1.4" thick
Thanks to O'Reilly for listing the dimensions of the filters I was able to find a filter right in that range from a Ford Mustang 2010-2013.
Using some general purpose weather strip and metal rods I was able to make a secure channel for it to sit in and close off the minor gaps.

2. To make replacement easy I knew I need a separate access panel that can be removed without taking off the entire panel with the blower motor etc.
I cut out the bulging portion of the panel where the condenser would normally reside.
Using some spare sheet metal I measured, cut and bent it to shape. 5 rotatable tabs and some grooves hold it in place and allow removal without tools.

3. Removing the bulging portion of the HVAC panel freed up some space. Removing some of the brackets and putting things closer to the wall gives a cleaner look in my opinion.

4. Lastly, the resistor. First off I moved it about 1.5" closer to the blower to provide ample space between the filter as well as get the resistor out of the way of the access panel. Next , using the screen found on the condenser I made a little barrier between the fan and resistor to catch debris. It is also removable with rotating tabs for easy cleaning and debris removal.

Pictures:

[This message has been edited by liv4God (edited 01-21-2021).]