this becomes something that either the two of you or the courts would end up deciding. Use of the easement is dependant upon the grant itself along with any supporting evidence (by the grantor) to determine the actual accepted use. If the car did not restrict your use of the easement, you might be hard pressed to do too much about it without any direction from the grant or the grantor.Yet, most ROW (or all?) are intended to be used for passage not parking right?
If it did restrict your use of the easement, this would almost assuredly be an improper use of the easement. The problem with this type of thing is that it generally requires a court to make the determionation and to enforce their orders (which you would have to motion for a contmept charge from the courts against the offender). Not a huge priority in the legal world.
what state is this in? laws are state specific and it may be possible for somebody to offer more direction if the state is known.

