When should I change my air filter?

[unique7]

I've had the car for about 2 years now and since then the air filter has never been changed. How often should it be changed and why should it be changed?
I looked at it and its not that dirty at all, just very slightly blacker but thats it, still relatively white.

[Stillrunning]

It's changed by miles not time and it is a judgement call depending on the dusty conditions you drive in. Usually if you can see a large % of light through it, it's OK. What does your owners manual say? Air filters are cheap so don't sweat it too much.

[unique7]

LOL, ownsers manual? the car is a 1997, you think I still have the owners manual :S...

God knows where it went, I bought it from someone with nothing in it, the car was dieing. I built the car so good it runs like new :-)

In fact, I spend more time and money on my car, once my girlfriend threatened to leave me. LOL. So I just pamper her(the car) when she aint around :P

[Jimnist]

Just change it, it's the only thing protecting your engine from dust, dirt e.t.c. Mine says every 20k km's.

Edit: my bad, it says to inspect every 2 500km's under dusty conditions, so replacing it every 5 000k's sounds okay (which is when i do my oil+filter).

[TheKevin]

if its a paper filter, i'd change it at every oil change or every other oil change.

for me, i have K&N filters(cone and drop in) on all my cars, so i clean it at every oil change.

[cruisn76]

Originally Posted by TheKevin

if its a paper filter, i'd change it at every oil change or every other oil change.

for me, i have K&N filters(cone and drop in) on all my cars, so i clean it at every oil change.

A little excessive no? Assuming you change your oil around 4-5k

[JCamry94]

Just get a K & N panel drop in filter and you don't need to change it ever, just clean it every 25,000 or so!

[Stillrunning]

Originally Posted by Jimnist

Just change it, it's the only thing protecting your engine from dust, dirt e.t.c.

Actually the dirtier it gets the better it filters. K&Ns will allow more dirt to get past filter, and if over oiled, oil as well.

[cruisn76]

Originally Posted by JCamry94

Just get a K & N panel drop in filter and you don't need to change it ever, just clean it every 25,000 or so!

I am assuming TheKevin runs through alot of dirt to be cleaning it that often. Especially a K&N filter. Otherwise 20-25k is good enough for a clean

[unique7]

Thanks guys, I guess I might as well get one seeing as though I have not changed it for about 2 years.

[desentrix]

Originally Posted by Stillrunning

Actually the dirtier it gets the better it filters. K&Ns will allow more dirt to get past filter, and if over oiled, oil as well.

If it's over-oiled, I'd be more concerned about it clogging the MAF.

[toyomoho]

Look at the filter and determine if it is dirty. What you see is what you have.