PACCAR PX-8 CM2150 (2007-09) Fault Code: 2451 PID: SPN: 2789 FMI: 0 Turbocharger Turbine Inlet Temperature (Calculated) – Data Valid but Above Normal Operational Range – Moderately Severe Level. Turbocharger turbine inlet temperature has exceeded the engine protection limit.

Verify the electronic control module (ECM) calibration is correct. Check the calibration revision history found on QuickServe™ Online for applicable fixes to the calibration stored in the ECM. If necessary, calibrate the ECM.

The most common cause of this fault code is low boost pressure. Low boost pressure can be caused by several factors; leaking charge air cooler, damaged charge air cooler piping or hose, loose charge air cooler clamps, damaged intake manifold pressure sensor, damaged variable geometry turbocharger, damaged turbocharger control valve, or damaged turbocharger control shutoff valve.

This fault code can also be caused by a turbocharger fuel control derate which can be viewed in INSITE™ electronic service tool under the Engine Operating State. Turbocharger fuel control derates can be caused by several factors: high exhaust temperatures, high turbocharger compressor inlet temperatures, and high turbocharger compressor outlet temperatures.

Exhaust gas recirculation (EGR) system leaks can also cause this fault code. Inspect the EGR bellows and EGR connections for signs of leaks.

Note: This fault code will most likely not be active with no load in the shop. The engine must be loaded to trip this fault code and to determine if the malfunction has been found and fixed. Running units on the dynamometer can sometimes cause this fault code to log due to the stationary nature and high temperatures.

Possible repairs:

1)Repair the leaking sealing surface(s).
2)Repair or replace the leaking component.
3)Tighten any loose clamps.
4)Replace the turbocharger.
5)Repair any leaks in the EGR system.
6)If necessary, calibrate the ECM.