What was found
(CAN) NR 2 ENGINE - STALL ECAM WARNING DURING ENGINE SPOOL-UP ON TAKE OFF ROLL. ON ENGINE INSPECTION, THEY FOUND THE PIVOT ATTACHMENT DETACHED , RESULTING IN VALVE NOT CLOSING , THE RESULT BEING H/P COMPRESSOR AIR BACK FEED TO THE I/P COMPRESSOR AIR CAUSING A COMPRESSOR STALL. THE ENGINE WAS INSPECTED IN ACCORDANCE WITH THE MAINTENANCE MANUAL. THE INTERMEDIATE PRESSURE CHECK VALVE WAS REPLACED AND A GROUND RUN WAS CARRIED OUT SERVICEABLE. NOTE: NR 1 ENGINE I/P CHECK VALVE WAS INSPECTED AS A PRECAUTIONARY MEASURE AND WAS FOUND SERVICEABLE.