I try to give my car a full run down once every other month. I check the fluid levels the tire pressure and hose down the engine bay (after making sure the engine is off and cool to the touch.) It keeps the car running smoothly and avoids that feeling of dread when you see the car is running a bit hot. (because you know it isn't your fault for not checking the coolant.)
***Note***
If you do wash down you engine bay please keep the position of you air intake in mind. It wouldn't be good for you to fill the intake with water.
