Cleaning your air filter?
I use 'Motor Saver' Filter exclusively on ALL of my Nitro vehicles (5). Clean and re-oil about every 4 races or so, depends how dirty the conditions.
Motor Spray to clean, blow dry with an Air Compressor and re-oil with Associated filter Oil (any THICK oil should work)
Once the Foam elements start to look crappy after cleaning, I just buy new ones.
'Dawn' and Hot water work equally as well for cleaning, just takes a little longer.