P0404 on Lincoln
Exhaust Gas Recirculation Circuit Range/Performance
P0404 on Lincoln vehicles indicates exhaust gas recirculation circuit range/performance. Au7o has documented this code across 1 Lincoln model — most commonly on Nautilus. This code means the exhaust gas recirculation (EGR) system isn't performing within its expected range. The EGR valve routes a metered amount of exhaust gas back into the intake to lower combustion temperatures and reduce nitrogen-oxide emissions, and the computer monitors the valve's actual position versus what it commanded. When the valve sticks, moves incorrectly, or the feedback doesn't match the command, P0404 sets. This can cause rough idle, hesitation, pinging, and increased emissions.
Common Causes of P0404
- •Carbon buildup clogging the EGR valve or passages
- •Sticking or failed EGR valve
- •Faulty EGR position sensor
- •Corroded or loose EGR connector
- •Damaged or shorted EGR wiring
- •Vacuum leak or failed vacuum control (on vacuum-operated systems)
- •Clogged EGR cooler or tubes
- •Faulty PCM/ECM (rare)
P0404 on Lincoln by Model
Lincoln Nautilus(1 issue)
- EGR Valve Failure Leading to Unexpected Loss of Drive Power (Recall 26S10 / NHTSA 26V122000)2025
Certain 2025 Lincoln Nautilus vehicles are part of Ford Motor Company's 26S10 recall. The exhaust gas recirculation (EGR) valve may fail, and the outcome NHTSA describes is an unexpected loss of drive power. Because the power loss can occur without warning, NHTSA cites an increased risk of a crash. The Nautilus is one of several 2025 Ford and Lincoln models in this single campaign, which totals 47,804 vehicles across all of them combined.
Looking for P0404 on a different make?
View P0404 across all makes →Frequently Asked Questions
What does P0404 mean on Lincoln?▼
P0404 stands for "Exhaust Gas Recirculation Circuit Range/Performance." This code means the exhaust gas recirculation (EGR) system isn't performing within its expected range. The EGR valve routes a metered amount of exhaust gas back into the intake to lower combustion temperatures and reduce nitrogen-oxide emissions, and the computer monitors the valve's actual position versus what it commanded. When the valve sticks, moves incorrectly, or the feedback doesn't match the command, P0404 sets. This can cause rough idle, hesitation, pinging, and increased emissions. On Lincoln specifically, this code is documented across 1 model.
What causes P0404 on Lincoln vehicles?▼
Common causes on Lincoln: Carbon buildup clogging the EGR valve or passages, Sticking or failed EGR valve, Faulty EGR position sensor, Corroded or loose EGR connector, Damaged or shorted EGR wiring. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P0404 on a Lincoln?▼
Repair costs vary widely depending on the root cause and specific Lincoln model.
Which Lincoln models have P0404 documented?▼
Au7o has documented P0404 on 1 Lincoln model: Nautilus.