my friend just bought a 90 EX for $700. it has a pretty bad leak from the oil pan gasket, we haven't gotten to replace it yet. the oil light is flashing, and from searching i keep seeing that the first thing to check is the oil pressure sending unit. according to the people she got it from, they just replaced it. now i know it could be a clogged oil pickup, or a dying oil pump, but could it be caused by a loss of pressure because of the leak at the oil pan? it's a pretty good sized leak... about 1 quart every 200 miles.

thanks, in advance.