P2457: How to Diagnose & Fix — Exhaust Gas Recirculation Cooling System Performance
4 vehicles · 4 makes · $500-$3,500 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 and restricts exhaust gas flow through the cooler core, and a cooler that overheats can 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 TSB 13-6-5 (superseding 12-6-14) covers 2011-2012 6.7L trucks with DTC P0401 and P2457, calling for EGR cooler core replacement under normal New Vehicle Limited Warranty coverage. 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+). For 2011-2012 trucks with DTC P0401 (Insufficient EGR Flow) and P2457 (EGR Cooler Performance), Ford TSB 13-6-5 applies; coverage follows the truck's normal warranty, so have a Ford dealer check the VIN. 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 (2)
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
Some 2.0L EcoBoost Nautilus SUVs may show low coolant, white smoke from the tailpipe, an over-temperature warning, an external coolant leak and/or a check-engine light with stored codes. Ford attributes this to the exhaust gas recirculation (EGR) cooler and/or PCM software settings. It affects 2019–2020 Lincoln Nautilus with the 2.0L EcoBoost engine; bulletin 20-2234 also covers the 2019–2020 Ford Edge 2.0L.
Common Symptoms
- Low coolant level
- White smoke from the tailpipe
- Over-temperature warning
- External coolant leak
- Check-engine light
How to Fix
Have a dealer confirm the symptoms and codes. Bulletin 20-2234 has vehicles built on or before 9-Jul-2020 get the latest PCM software first, then a cooling-system pressure test and inspection of the EGR cooler for damage or internal leaks; if the EGR cooler leaks, the EGR cooler and EGR outlet tube are replaced. If the cooler does not leak, the technician follows standard workshop-manual diagnosis. Normal warranty rules apply; this is not a recall or a promise of free repair.
Sources for this issue (2)
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 $3,500, 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.
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Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.