N1
Torque
Engine
Temperature Probable
Cause
Correct
Low
High
Dirty inlet and/or compressor Bleed bend leaking Leaks in anti–
icing
FOD
Erosion Damaged combustor section PTIT indicating system Combus-
tion chamber drain valve open
Low
Low
Low
Calculation error Engine not properly topped Fuel control adjustment
High
Correct
High
Calculation error Fuel control adjustment
Correct
Correct
High
N1 indicating system error
Correct
Low
Correct
Torque indicating system Torque transmitter malfunctioning
Correct
Correct
Low
PTIT indicating system
Figure 5-16. Turbine Engine Analysis Check Troubleshooting Chart
