PACCAR MX (2004 Emissions) Fault Code: P1498 EGR Valve Position – Incorrect

Description

PACCAR MX (2004 Emissions) Fault Code: P1498 EGR Valve Position – Incorrect

SET CONDITIONS:
The PCI ECU (D420) detects that the actual position of the EGR valve deviates too much from the requested position for more than 2 seconds.

DIAGNOSTIC CONDITION:
This diagnostic runs continuously while the engine is running, except when the engine is running in Engine mode ‘SCR Heating’.

CORRESPONDING OBD READINESS MONITOR:
None

RESET CONDITION:
The DTC changes to inactive after the diagnostic runs and passes.

REPAIR VERIFICATION:
1. Clear all DTCs.
2. Test drive or operate the vehicle to meet the diagnostic conditions and set conditions.
3. Did the DTC come back?
– No, repair successful
– Yes, repair unsuccessful

POSSIBLE CAUSES:
Bent connection rod between the valve and the actuator motor

Stuck EGR valve due to:
1. Contamination on the mechanism
2. Expansion/contraction of the valve housing due to sudden temperature differences (temporary situation)