Toyota Repair: 98 Toyota Avalon XLS, toyota avalon, resorvoir

Question
I recently noticed that the front drivers side suspension makes a funny sound when hitting rough or bumpy roads. But, during rainy or cold days it doesn't occur.  I'm assuming a new strut.  Also, when setting the ventilation system to recirculate with the fan off, it still allows fresh air to enter. The XLS has the automated climate controls if that helps. Last, the coolant resorvoir has about a 1 inch diameter of dried up coolant around the edge of the cap. I tried taking the cap off and putting it back on.  Seems normal, not loose at all.  What would cause this.  Thanks in advance.

Answer
Usually this noise is coming from worn strut upper mounting brackets and replacing them takes care of the noise, the struts do need to be removed to replace them, if it has lots of miles(past100,000) I recommend replacing the struts also.
A small amount of fresh air will always enter the passenger compartment regardless of the setting so this may be normal.
Cleaning the coolant bottle and changing the coolant seems to help this especially if it has the red coolant which for some reason tends to do this, change the coolant with green antifreeze, that should solve this. Make sure the bottle is at the full mark and not overfilled.