How often do you need to clean the filter on these things?

 

I like to clean mine every time Spring comes around.

 

No set time or miles, if it looks dirty then clean it.

I cleaned mine after about 10k miles.

If you don't care that it turns red just get the K&N re-charge kit from a local auto store.

 

I just cleaned mine with the K&N re-charge kit and I'm more than happy with it. The filter did not look too dirty but once I started washing it I couldn't believe how much dirt got accumulated in the filter. Just make sure to let it sit and dry for couple of days once washed to get all the water out, plus let it sit when you reoil the filter. IMPORTANT: DO NOT OVER OIL IT. It will kill your MAF.

 

ummmm? Is that a serious question