What was found
(CAN) AIRCRAFT IS EQUIPPED WITH AN AFTERMARKET 6 CYLINDER EXHAUST GAS TEMPERATURE ENGINE MONITOR. DURING BREAK-IN PERIOD FOR FACTORY REMANUFACTURED ENGINE, NR 4 CYLINDER EGT RAN 200 DEGREES F HIGHER THAN THE OTHER FIVE CYLINDERS. TROUBLESHOOTING EVENTUALLY FOUND A PLUGGED INJECTOR LINE TO NR 4 CYLINDER. PLUG WAS AN UNKNOWN WHITE POWDERY MATERIAL. PLUG WAS REMOVED, LINE CALIBRATED, ENGINE RETURNED TO SERVICE. NR 4 CYLINDER EGT NORMAL. CESSNA ENGINE GAUGES READ NORMAL BEFORE AND AFTER PROBLEM AND DID NOT INDICATE A PLUGGED FUEL LINE.