ok, as far as I know there is no cabin air filter in my 2002 H1, correct?

has anyone come up with a filter they made or anything? I'm in the desert and dust blows out the vents

ideas, solutions?

 

Most likely you would need to remove the HVAC box and disassemble to try and install a filter of some kind. This is kinda a major job and the box is very fragile and expensive if broken. (Big Dog Offroad has one of the last complete hvac units). I would make sure the recirculate / fresh air blend door in the hvac box is always in the recirculate position. I would ziptie the door lever, plug the vacuum line and disconect it. You could try and remove the blower motor and install a filter thru that hole but you will need a good masage to get the kink out of your nexk after standing on your head to do it. And if the filter is before the fan and it comes apart and goes thru /into the fan that would really suck.

 

You'd need a new design HVAC box as Ian Ward pointed out the factory one is crammed pretty tight.

One option is to come up with a method of installing a filter on the body side of things, the air inlet is on the side of the passenger body panel where the mushroom cap intake is. The air coming in through the cap on the top goes to the engine/ctis system, etc. The air on the side vent gets sucked into the HVAC system. There isn't much clearance and it would be an R+D project to try to get something to work there plus some body modification work.