PACCAR MX (2004 Emissions) Fault Code: P1191 Fuel Filter – Clogged
PACCAR MX (2004 Emissions) Fault Code: P1191 Fuel Filter – Clogged
SET CONDITIONS:
The PCI ECU (D420) detects that:
1. Fuel temperature is more than 95?C [203?F] and
2. Fuel pressure is too low
DIAGNOSTIC CONDITION:
This diagnostic runs continuously when the engine is running.
CORRESPONDING OBD READINESS MONITOR:
None
RESET CONDITION:
This DTC changes to inactive when the fault is no longer detected.
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:
Clogged fuel filter
ADDITIONAL INFORMATION:
1. The low-pressure fuel pressure is measured by the fuel pressure sensor (F801).
2. The low-pressure fuel temperature is measured by the fuel temperature sensor (F803).
