Try bleeding the brakes before you start throwing parts at the problem. If it becomes a chronic problem, it's probably time for a new MC, as the failure rates of those third world parts are almost as bad as condensers. Be sure to bench bleed a new one before installing it.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!