As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT 4151 - DURING FLIGHT, LT ENGINE NH GAUGE BECAME ERRATIC, CREW INSTRUCTED TO RETURN TO FIELD. AIRCRAFT LANDED WITHOUT FURTHER INCIDENT. PIT/MX REPLACED LT ENGINE NH PULSE PICK-UP IAW MM 77-00-00. OPS CHECKED GOOD, AIRCRAFT RETURNED TO SERVICE.