What was found
CABIN ALT WARNING AT FL 380. CAB ALT INDICATED + 10000FT. OUT FL OW VALVE SHOWED FULL CLOSED. WHILE PERFORMING OUTFLOW VALVE TEST FOUND VALVE MOVEMENT ERRATIC WHEN COMMANDED. SUGGEST REPLACEMENT OF OUTFLOW VALVE PER 21-31-03-402-010. REMOVED AND REPLACED CABIN PRESSURE OUTFLOW VALVE. REF AMM DURING EXCESSIVE CABIN PRESSURE LEAKAGE TEST AMM FOUND CABIN AIR SUPPLY CHECK VALVE BOOT IN LEFT PACK 21-31-03-402-010. OPS NORMAL. R & R PRESSURE RELIEF VALVE UP TO STEP F (9) REF. AMM 21-32-01-402-009. LOWER RELIEF VALVE PASSED TEST REF. AMM 21-32-01-702-38. PERFORMED POSITIVE PRESSURE RELIEF VALVE TEST ON UPPER RELIEF VALVE. TEST PASSED.