Air circuit and EGR fault finding

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ThoreT
Donor 2023
Posts: 11
Joined: 12 Jun 2023, 11:28
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Air circuit and EGR fault finding

Unread post by ThoreT »

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My 2.7 HDI suffers from power loss and uneven running during acceleration. Prime suspect is of course an EGR valve. I connected my code reader to check running parameters. See attached pictures. There are three different parameters related to each EGR.

The rear EGR Valve Position 1 Setting (Rear) is stuck at 50%, regardless of power-setting. I guess this means the rear EGR valve is physically stuck at 50% open. The two other values, EGR Valve Control 1 (Rear) and EGR Valve Position 1 (Rear) both follow power-setting in a sensible way, and drop to around 5% after one minute at idle. One of the values I'm sure refers to the input value from the ECU, what but is the third parameter? I would think there would be only two parameters, one for input value and one for actual physical EGR valve position.

The picture showing Air Flow parameters shows a low rear air flow, which makes sense.

Strangely, I get no fault codes for the EGR, only messages related to low airflow and airflow incoherence. Also, when I ran the EGR actuator check in Diagbox, I got no error message, but I could not hear the valve clicking.

Hopefully a new rear EGR will get me going again....
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