Technical EGR fault codes

[jav225566]

Hi everyone,


Any idea what I should check next? These codes keep coming back and are constantly being logged in the ECU:

• P0490 – Exhaust gas recirculation (EGR) system – circuit high (electrical fault output 2 DC motor EGR)
• P0487 – Exhaust gas recirculation (EGR) system, throttle position control – circuit malfunction (EGR position derives positive DC motor, opening insufficient)

I have already cleaned the EGR valve and checked the control mechanism coil—everything seems to be functional. However, after clearing the faults, I only need to drive a few kilometers before they reappear.


Other symptoms include increased exhaust smoke, an unstable/surging idle, and possibly higher fuel consumption.


Thanks for any advice!

 

[jackwhoo]

Replace egr valve with a good brand NEW part

 

[AnthonyH]

Hi everyone,


Any idea what I should check next? These codes keep coming back and are constantly being logged in the ECU:

• P0490 – Exhaust gas recirculation (EGR) system – circuit high (electrical fault output 2 DC motor EGR)
• P0487 – Exhaust gas recirculation (EGR) system, throttle position control – circuit malfunction (EGR position derives positive DC motor, opening insufficient)

I have already cleaned the EGR valve and checked the control mechanism coil—everything seems to be functional. However, after clearing the faults, I only need to drive a few kilometers before they reappear.


Other symptoms include increased exhaust smoke, an unstable/surging idle, and possibly higher fuel consumption.


Thanks for any advice!

Circuit high often means the wires are broken and not even connected. You need to check that the electrical circuit is working properly.

 

[AnthonyH]

Do check that you have plugged the EGR back in, i forgot to plug mine back in just a few days ago!

 

[jav225566]

The connector is plugged in properly. However, I only tested the functionality on the bench. It didn't cross my mind that there could be an issue with the wiring itself.


I need to find out how to test the wiring harness.