As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
UPON TAXI OUT "A" F/A REPORTED HAZE IN THE FWD CABIN AND THEN AN ACRID SMELL. WHEN REPORTED, BOTH ENGINES WERE RUNNING AND APU WAS SHUTDOWN. 5 PLUS MINUTES HAD LAPSED WHEN REPORT WAS RECEIVED AND WE HAD JUST BEEN CLEARED FOR T/O. CABIN ODOR WAS HYD FLUID, FOUND CAUSE TO BE HYD PUMP LEAK AT ENGINE NR 2. SECURED LEAKING LINE.