cold air intkae

how often should u change the filter on ur cold air intake?

Depends what kind of filter you have. Some are cleanable, some you must replace. K&N are cleanable and have 'recharger' cleaning kits available...they recommend cleaning them every 15k unless you live in a very dusty climate.

HKS I think need to be thrown out and replaced.

What do you have?

Hold the element up to a bright light or the sun, and look through it from the inside out. If the media looks pretty transparent to the light, it's OK. If it's pretty dark, it's done. Clean or replace, like 500 said.