What was found
LGA - FLT 4844 - BLUE ADVISORY MESSAGE E1 HYDRAULIC PUMP FAIL. FOLLOWED AIRCRAFT OPERATING MANUAL AND TURNED ON NR 1 ELECTRIC HYDRAULIC PUMP. NR 1 ELECTRICAL HYDRAULIC PUMP. NR 1 HYDRAULIC SYSTEM FAIL ILLUMINATED AND NR 1 ELECTRIC HYDRAULIC PUMP WAS TURNED OFF. TURNED ON NR 1 ELECTRIC HYDRAULIC PUMP DURING APPROACH. SYSTEM PRESSURE RESTORED, E1 HYDRAULIC PUMP FAIL MESSAGE EXTINGUISHED. AFTER LANDING LOST NR 1 HYDRAULIC SYSTEM PRESSURE. LOST NOSE WHEEL STEERING WHEN NOSE LANDING GEAR TOUCHED DOWN. (M)