Living in a region where road salt is used I do clean the front carpet every few years. I mean that I remove the carpet and under pads and wash these with soap. It takes just 15 minutes to remove, other posts describe how to do it.

I lay the carpet on a polythene sheet on the driveway asphalt. I use the garden hose to rinse well and hang to dry in the sun.

Good occasion to check for water leaks while you drive a couple days without carpets, under the rain if possible.

Roland