PACCAR PX-8 CM2150 (2007-09) Fault Code: 1899 PID: 411 SPN: 411 FMI: 1 Exhaust Gas Recirculation (EGR) Valve Delta Pressure – Data Valid But Above Normal Operating Range – Moderately Severe Level. The EGR differential pressure sensor has detected low EGR gas flow or the EGR differential pressure reading is not valid for engine operating conditions.

Description

Verify the 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.

This diagnostic checks the EGR differential pressure sensor reading when the EGR valve is open. Since the EGR valve is open, the reading of the EGR differential pressure must be greater than zero. If the ECM detects a reading lower than expected with the EGR valve open, this fault code is logged.

Possible causes:

1)A malfunctioning EGR differential pressure sensor
2)A stuck closed EGR valve
3)EGR differential pressure sensor flow port cross-drillings are plugged with soot or shellac
4)A fouled EGR cooler.

Possible repairs:

1)Clean the EGR differential pressure sensor flow ports.
2)Clean the EGR cooler.
3)Replace the EGR delta pressure sensor.
4)Repair or replace the engine harness.
5)Replace the ECM.