What does the PTC do and does it come off?

[gotmeaT-5]

Everywhere I go there are statements about a thing called "The PTC" is this is it, what does it do and how do I remove it for cleaning ? Mine is gunged up and I wonder if it will help to my terrible fuel economy on my 850 T-5

[Rnash2002]

Its to do with the pcv sytem,i think i read it warms up so keeps the oil flowing through it?.
the hole rubber thing its in will twist then you pull it out,it will seem pritty tight but does come out.