We propose four 20 ksec observations of the northeastern limb of the Cygnus Loop supernova remnant to study a recently discovered carbon rich region. This region seems to be the result of the interaction between the shock and an interstellar cloud or the cavity wall. Because of the superior spectral resolution and low background of the XIS in the low energy region, these pointings can also be used for the study of the C-N-O abundance ratio of the ISM in the vicinity of the Loop.