As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PDX-INTERMITTANT AMBER LOW PRESSURE MESSAGE ON FUEL SYNOPTIC PAGE. THE MESSAGE WAS NOT ACCOMPANIED BY ANY CAUTIONS OR WARNINGS. REPLACED LEFT HAND ENGINE INLET PRESSURE SENSOR. OPERATIONAL CHECK GOOD. NO LEAKS. GROUND RAN ENGINES AND NO TOGA FAULT APPEARED. AIRCRAFT RETURNED TO SERVICE.