EGR valve

P2457 EGR cooler: reading or operation not right

By: Diagno editorial team · Updated: 2026-10-15

P2457 means: EGR cooler: reading or operation not right. The EGR valve sends part of the exhaust back into the intake to cut emissions. OK to drive, but have it checked soon. The repair usually costs about €80–700 in Estonia. The most common cause: EGR valve clogged with soot.

Is it safe to drive?OK to driveOK to drive, but have it checked soon.

Typical repair cost€80–700parts and labour in Estonia

What it means

The EGR valve sends part of the exhaust back into the intake to cut emissions. The computer found too much or too little flow, or a fault in the valve's electrics. There is a signal, but the reading or operation isn't plausible. The cause may be the part itself or a real mechanical fault.

What you may notice

Engine light on
Less power
Rough idle
Black smoke on diesels

What could be wrong

1EGR valve clogged with soot
2EGR passages or cooler blocked
3Faulty valve position sensor or motor
4Vacuum hose or solenoid (older cars)

Repair difficulty: Moderate

What you can check yourself

Lots of short trips clog the EGR quickly. Sometimes a longer motorway drive helps. You can check the simple things yourself, but the repair is best done in a workshop.

How we fix it

We check valve operation with the diagnostic tool
We clean the valve and passages
We replace the valve if cleaning isn't enough

Standard SAE description: Exhaust Gas Recirculation Cooling System Performance

This code usually comes with: Check engine lightSee what the light means →

Related symptoms: Smoke from the exhaust · Rough idle or engine stalling

Want a definite answer?

Bring the car to our workshop in Estonia for diagnostics. We read the fault codes, test the sensors and tell you what is wrong. Repair price depends on the work involved, generally €45 per hour.

Book a diagnostic check

Questions

What does fault code P2457 mean?

EGR cooler: reading or operation not right. The EGR valve sends part of the exhaust back into the intake to cut emissions. The computer found too much or too little flow, or a fault in the valve's electrics. There is a signal, but the reading or operation isn't plausible. The cause may be the part itself or a real mechanical fault.

Can I drive with code P2457?

OK to drive, but have it checked soon.

How much does it cost to fix P2457?

Roughly €80–700 in Estonia. The price depends on exactly what has failed and on the car.

How is P2457 fixed?

We check valve operation with the diagnostic tool. We clean the valve and passages. We replace the valve if cleaning isn't enough.

Based on AI combined with our hands-on workshop experience and knowledge. This information is general and prices are approximate (Estonian workshop rates). The same code can mean different things on different cars. Only an inspection of the car gives a definite answer.