Fault code P2457

[GLC1980]

Hi all, I’ve just had the engine management light come up and it is Fault code P2457 egr cooling system - performance problem, has anyone had any issues with this and is it an easy fix or anything I can do to clean egr system out etc, can has been driving fine and don’t do any short runs at low revs or anything, it’s 2018 150 with 64k on the clock.
Thanks for any help

 

[mmi]

the engine management light

Flashing glow light or emission light (=engine symbol)?

P2457 egr cooling system - performance problem

Possibly "pump for exhaust gas recirculation cooler (V400)" is not performing well enough?
Does your diagnostic tool read also VW specific codes to detect component failures, or only generic OBD codes (emission)? Just to make sure there isn't altready a code related to the pump?
Can you read coolant temperatures in and out of the cooler?
Expected behaviour explained in below

Post in thread '[T6_measured] Winter specialities'

6 Dec 2023

Reserved.... EGR, EGR cooling, EGR bypass...

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❆❆ EGR normal cooling and EGR cooler bypassed​

From 0 to 200 seconds reported EGR position > 0% thus EGR cooler bypassed. This cooler bypass happens always after engine start, even in summer conditions. [EDIT: 20.4.2024]

From 200 to 1100 seconds reported EGR position < 0% thus exhaust recirculation through EGR cooler.

From 1100 to 1800 seconds reported EGR position > 0% thus EGR cooler bypassed (also seen from 0 to 200 seconds).

The transition seems to take place somewhere at 0....+5 °C.

EGR position...​

• mmi

• 
• 

 

[GLC1980]

Flashing glow light or emission light (=engine symbol)?


Possibly "pump for exhaust gas recirculation cooler (V400)" is not performing well enough?
Does your diagnostic tool read also VW specific codes to detect component failures, or only generic OBD codes (emission)? Just to make sure there isn't altready a code related to the pump?
Can you read coolant temperatures in and out of the cooler?
Expected behaviour explained in below

Post in thread '[T6_measured] Winter specialities'

6 Dec 2023

Reserved.... EGR, EGR cooling, EGR bypass...

---

❆❆ EGR normal cooling and EGR cooler bypassed​

From 0 to 200 seconds reported EGR position > 0% thus EGR cooler bypassed. This cooler bypass happens always after engine start, even in summer conditions. [EDIT: 20.4.2024]

From 200 to 1100 seconds reported EGR position < 0% thus exhaust recirculation through EGR cooler.

From 1100 to 1800 seconds reported EGR position > 0% thus EGR cooler bypassed (also seen from 0 to 200 seconds).

The transition seems to take place somewhere at 0....+5 °C.

EGR position...​

• mmi

• 
• 

Hi, no it’s just a cheap code reader that just throws up a code, there’s been no other codes came up just the one about the cooling so assumed it wasn’t directly related to the egr itself, I’ve put a cleaner through it juts in case and then reset it so will keep an eye on it to see if it comes up again