Our SAAB 900s has a K&N drop in air filter, it is very dirty, any ideas on how to clean it? Must I buy the K&N solution and oil to clean it?

 

The K&N kit is what is used to clean their filter, the only cleaner to use.
Spray down the filter with the K&N cleaner, use a small one inch paint brush to assist in bug removals. Allow to rest for ten minutes.

Use hose pressure without a nozzle to rinse from the inside out. Be careful not to damage the cotton gauze in the filter. Allow to air dry, don't use compressed air or a hair dryer. It may damage the cotton. Water doesn't mix with the oil used in the next step.

Next is the tricky part, re-oiling the filter using the K&N filter oil. A thin coat of the outside surface is sufficient. Too much oil causes problems with the air sensors, part of the fuel control system. A light pink color on the outer gauze is good. If you use too much, clean with the cleaner, rinse, dry and re-oil.

I usually go once all the way around, then quickly touch up as needed.

Vacuum the inside of the air filter container prior to the filter replacement.

 

Thanks for the detailed intel.