P2457: How to Diagnose & Fix — Exhaust Gas Recirculation Cooling System Performance
4 vehicles · 4 makes · $500-$9,000 repair
How to diagnose and fix P2457: most-reported vehicles
Ranked by owner reports. Each card gives the symptoms, how to confirm the cause, the fix, parts and sources for that vehicle.
Ford F-250 Super Duty · 2011–2019
The EGR (Exhaust Gas Recirculation) cooler on 2011-2019 6.7L Power Stroke diesel engines is prone to clogging with soot and eventually failing, particularly on trucks used for highway driving, light loads, or trucks that idle extensively. The EGR cooler recirculates cooled exhaust gas back into the intake to reduce NOx emissions. Over time, soot accumulates in the cooler's internal passages until coolant flow is restricted, causing the cooler to overheat and fail. When it fails, exhaust gases enter the coolant system, causing overheating and "puking" coolant from the degas bottle. The 2011-2014 models are particularly susceptible due to narrow internal coolant passages. Ford issued TSBs for 2011-2014 trucks covering EGR cooler cleaning/replacement under extended warranty up to 120,000 miles. The EGR cooler for 2011-2016 is OEM part BC3Z-9V425-A; 2017+ is HC3Z-9V425.
Common Symptoms
- Coolant loss with no visible external leak
- Coolant reservoir overflows or "pukes" coolant
- White smoke from exhaust (coolant in combustion)
- Engine overheating warning
- DTC codes P0401 (Insufficient EGR Flow) or P2457 (EGR Cooler Performance)
- Bubbling or foaming in coolant degas bottle
- Loss of power under load (especially towing)
- White deposits around degas bottle cap
How to Fix
Replace EGR cooler (BC3Z-9V425-A for 2011-2016; HC3Z-9V425 for 2017+). Check if truck qualifies for Ford extended service coverage with active DTC P0401 (Insufficient EGR Flow) or P2457 (EGR Cooler Performance). Some 2011-2014 trucks covered to 120,000 miles. Preventive: use a fuel additive (Diesel Kleen, Hot Shots Secret EDT) to reduce soot. Perform regular EGR cleaning at 60,000-mile intervals. Upgrade kits from Sinister Diesel and Dorman (904-405 kit) include both EGR cooler and gaskets.
Sources for this issue (1)
BMW 7 Series · 2015–2015
The 740Ld xDrive uses the N57 inline-six diesel, whose EGR cooler can crack and leak coolant internally. The coolant mixes with diesel soot inside the EGR path, and at high EGR gas temperatures those wetted soot particles can smolder, melting the plastic intake manifold and creating a risk of underhood fire. NHTSA recall campaign 18V-755 (October 2018) covered 2013-2017 BMW diesels including the 2015 740Ld, and recall 21V-907 (November 2021) superseded and expanded it to roughly 50,400 vehicles, re-including every car previously covered by 18V-755. This is an active fire-risk recall, not a nuisance item.
Common Symptoms
- Unexplained coolant loss with no visible external leak
- White smoke from the exhaust
- Burning smell from the engine bay
- Reduced power or limp mode
- Check engine light
How to Fix
Take the VIN to a BMW dealer under recall 21V-907 - the repair is free. Dealers inspect and replace the EGR cooler; if a leak has already occurred, the intake manifold is replaced as well. Verify status by VIN at nhtsa.gov/recalls, since a car repaired under the earlier 18V-755 campaign is still covered by the 2021 expansion. Do not dismiss unexplained slow coolant loss with no external leak on an N57 diesel - that is the leading indicator.
Call to confirm they can assess your vehicle and perform the stated work. Search results do not confirm qualification, eligibility or coverage.
Sources for this issue (3)
Lincoln Nautilus · 2019–2020
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.
Common Symptoms
- Repeated low-coolant warnings / disappearing coolant with no visible leak
- White smoke from the tailpipe (especially on cold start)
- Engine overheating / over-temperature warning in cluster
- Sweet coolant smell inside or outside the vehicle
- Rough idle and misfires (coolant-fouled plugs)
- Check engine light
How to Fix
Per TSB 20-2234, perform a cooling-system pressure test and inspect the EGR cooler; replace the EGR cooler and update PCM software for the typical case. If a coolant smell, white smoke, and cylinder misfires persist (coolant intrusion past the head gasket), the durable fix is a long-block / engine replacement with the updated cross-drilled block — a head-gasket-only repair on the old-style block will fail again. Replace fouled spark plugs and flush the cooling system.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- Genuine Ford K2GZ-9F464-B EGR coolerOEMK2GZ-9F464-B
Replace a cooling-system-pressure-test-confirmed internally leaking EGR cooler under the matching TSB branch Fitment/availability: Live Ships in 1-3 Business Days/Add to Cart page identifies K2GZ-9F464-B, replacement of K2GZ-9F464-A and …
- Genuine Lincoln CYFS-12Y-PCTX / Motorcraft SP-550X spark plugOEMCYFS-12Y-PCTX / SP-550X
Confirm VIN
- Motorcraft Yellow prediluted antifreeze/coolant VC-13DL-G, 1 gallonOEMVC-13DL-G
Refill and bleed the repaired system with Ford-approved service coolant after the leak is corrected Fitment/availability: Live In Stock/Add to Cart direct page identifies Motorcraft VC-13DL-G one-gallon yellow prediluted coolant. Ford ap…
As an Amazon Associate, we earn from qualifying purchases; other part links may also earn au7o a commission. Confirm fitment by VIN before buying.
Sources for this issue (3)
RAM 2500 · 2007–2024
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P2457 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P2457 mean?
P2457 stands for "Exhaust Gas Recirculation Cooling System Performance." Generic code set when the PCM determines the EGR cooler/cooling system is not lowering recirculated exhaust gas temperature as much as expected — the cooler is underperforming, often due to clogging, coolant flow loss, or a stuck bypass.
What are the most common causes of P2457?
The most common causes of P2457 are: Carbon-clogged/restricted EGR cooler, Loss of coolant flow through the cooler, Stuck EGR cooler bypass valve, Faulty temperature sensors used for the monitor. The specific cause varies by vehicle.
How much does it cost to fix P2457?
Repair costs for P2457 range from $500 to $9,000, depending on the vehicle and root cause.
Which vehicles are affected by P2457?
Au7o has documented P2457 across 4 vehicle models from 4 manufacturers: BMW, Ford, Lincoln, RAM.
Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.