I am just learning how to work on my 1990 ac. int. ls 4 door... Inside there are 3 small pipes...1 is about an 1/8 inch thick and the other two are about 1/4 inch thick...They are directly placed on top of each other with the smaller pipe on top...I noticed a large puddle of drty radiator water underneath my car...It needs a good flush...When the car gets heated to running temp. the pipe on the bottom starts to spit out this dirty water/fluid...the pipes connect to the air filter tube and the one on the bottom goes to the engine closer to the bottom where the thermostat is...the top pipe goes to the near the throttle body is...i cannot remember where the other one goes...My question is what are the names of these pipings? What do they do? How can I replace them if a can actually do it myself? Will I have to continually put water or fluid in my radiator to drive if indeed driving is o.k.? Since I am still learning I am very eager to find out as this will be a learning opprtunity...Trying to stay positive about the situation!!!