What was found
ISSUE-CREW REPORTED ON CLIMB OUT AT FL180, PERFORMED ICE DETECTION TEST WITH NORMAL PARAMETERS. TESTED OK, WENT BACK TO ICE DETECTION AUTO. ENG 1 A/ICE FAIL EICAS DISPLAYED. ENG 1 ICE VALVE STAYED OPEN. RAN QRH AND MESSAGE PERSISTED. A/ICE FAIL MESSAGE ANNUNCIATED. RAN QRH FOR THAT AND FELT A SUDDEN SHUTTER/VIBRATION OF ENTIRE AIRCRAFT. ENG INDICATIONS ALL LOOKED NORMAL AND GREEN. VIBRATION NO LONGER PERSISTED. DIVERTED BACK TO LAS AND ON DESCENT MESSAGES WENT AWAY. NORMAL LANDING. CORR ACTION- MX FOUND ONE CLAMP ON STARTER CONTROL VALVE LOOSE AND LEAKING. R&R'D CLAMP INSPECTED ALL OTHER ENG 1 BLEED LINES WITH NO FURTHER DEFECTS NOTED. PERFORM BLEED LEAK AND OPS TEST NO DEFECTS NOTED. PERFORMED A/I OPS TEST NO DEFECTS NOTED. ELECTED TO PERFORM AN OCF TO ENSURE NO FURTHER VIBRATIONS OR SHUTTERS FELT. COMPLETED OCF WITH NO DEFECTS NOTED AIRCRAFT RELEASED.