I am looking at new air filters to put in my IS250.

I am going to buy the K&N Air Filter, but my dad is concerned that it would be a bad purchase if my car has an Intake Sensor.

Input?

 

Intake sensor? Might be refering to a Mass Airflow Sensor.. If you over-oil a K&N filter, they are known to get oil on the sensor which can mess with the readings. Out of the box, the filters are oiled fine. I havent had any issues with mine yet.

 

My experience is the same. Been using K&N for about 16 years. Oil it just enough to cover the the white spots on the filter. Dont put it in right after oiling either. Give it a day or so and let it soak in.