As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PILOT REPORTED THAT IDLE RPM WAS TOO HIGH, 850 RPM. WHILE TECH WAS TRYING TO ADJUST IDLE, FOUND THAT THE FUEL PRESSURE WAS LOW - 16 PSI AND UNABLE TO ADJUST. REPLACEMENT OF ENGINE DRIVEN FUEL PUMP WAS REQUIRED. RECOM TO ADD A METHOD PLUS DATA FOR MAKING ADJUSTMENT IN THE FIELD. (K)