P044C on Lincoln
Exhaust Gas Recirculation Sensor "C" Circuit Low
P044C on Lincoln vehicles indicates exhaust gas recirculation sensor "c" circuit low. Au7o has documented this code across 1 Lincoln model — most commonly on Nautilus. A generic (SAE-defined) powertrain code that applies to 1996-and-newer vehicles of any make. The engine control module has detected a lower-than-expected voltage on the circuit for EGR sensor "C" — depending on the platform this is an EGR valve position or EGR temperature sensor. The EGR system recirculates a metered amount of exhaust back into the intake to lower combustion temperature and NOx, so a faulty feedback signal means the module cannot verify EGR flow. Expect a check engine light, possible rough idle, hesitation, or reduced fuel economy, and the vehicle will fail an OBD-II emissions test while the light is on. Typical repair costs on Lincoln range from $600 to $9,000, depending on the specific model and root cause.
Common Causes of P044C
- •Failed EGR position or EGR temperature sensor providing incorrect feedback
- •Short to ground or open in the sensor signal or reference wiring
- •Corroded, damaged, or loose connector at the EGR sensor
- •Carbon buildup in the EGR valve, passages, or cooler causing the valve to stick
- •Faulty EGR valve assembly with an integrated sensor
- •Exhaust or intake leak near the EGR circuit skewing readings
- •Failed ECM/PCM (rare — verify sensor and wiring first)
P044C on Lincoln by Model
Lincoln Nautilus(1 issue)
- 2.0L EcoBoost coolant loss / EGR cooler leak — low coolant, white smoke, overheat2019-2020
2019-2020 Nautilus models with the base 2.0L EcoBoost (non-hybrid) suffer unexplained coolant loss, white tailpipe smoke, an overheat warning, and sometimes coolant intrusion into the cylinders. Ford TSB 20-2234 traces the most common cause to a failing exhaust gas recirculation (EGR) cooler that leaks coolant internally; the related design also has a known coolant-intrusion weakness (narrow coolant slit between cylinders compromising the head-gasket seal). Owners report repeated coolant top-offs with no visible external leak, then misfires as coolant fouls the plugs. A June 2025 Ford EcoBoost coolant-intrusion class action covers 1.5L-2.0L engines; the most severe Nautilus cases require engine replacement with the redesigned block.
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View P044C across all makes →Frequently Asked Questions
What does P044C mean on Lincoln?▼
P044C stands for "Exhaust Gas Recirculation Sensor "C" Circuit Low." A generic (SAE-defined) powertrain code that applies to 1996-and-newer vehicles of any make. The engine control module has detected a lower-than-expected voltage on the circuit for EGR sensor "C" — depending on the platform this is an EGR valve position or EGR temperature sensor. The EGR system recirculates a metered amount of exhaust back into the intake to lower combustion temperature and NOx, so a faulty feedback signal means the module cannot verify EGR flow. Expect a check engine light, possible rough idle, hesitation, or reduced fuel economy, and the vehicle will fail an OBD-II emissions test while the light is on. On Lincoln specifically, this code is documented across 1 model.
What causes P044C on Lincoln vehicles?▼
Common causes on Lincoln: Failed EGR position or EGR temperature sensor providing incorrect feedback, Short to ground or open in the sensor signal or reference wiring, Corroded, damaged, or loose connector at the EGR sensor, Carbon buildup in the EGR valve, passages, or cooler causing the valve to stick, Faulty EGR valve assembly with an integrated sensor. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P044C on a Lincoln?▼
Repair costs on Lincoln range from $600 to $9,000, depending on the specific model and root cause.
Which Lincoln models have P044C documented?▼
Au7o has documented P044C on 1 Lincoln model: Nautilus.