Question about EGR solenoid circuitry

[uzigon]

I've bought a second hand 2010 Citroen C4 Picasso around the 200,000 km mark and there are several jobs I have been undertaking in an effort to keep this odd but practical vehicle on the roads.

I had an question about the function of the EGR valve. I was noticing some behaviour from the vehicle that suggested a problem with the EGR, so dismantled is for cleaning - which it was well due for. I had concern about some of the circuitry in the top part of the solenoid, mine seems to be completely gone as seen in the photo.

When I compared to a DIY video, the difference is obvious.

I feel like I will should be replacing the solenoid part, the rest of the valve assembly is fine.

Does anyone know what this circuitry is for and how would having it broken impair function?

[wheeler]

The circuitry will be for position feedback, a simple potentiometer setup so the ECU can check that the valve is doing what it is asking.

[uzigon]

That is kind of what I was thinking, but I wasn't sure how this would affect operation. I have received no DTCs since cleaning, refitting the part and driving around the county for the day.

Any clue as to what would happen if the position couldn't be detected by the ECU? Would the valve still open as normal?

[wheeler]

I have received no DTCs since cleaning, refitting the part and driving around the county for the day.

Maybe the previous owner has done you a favour as i would expect to see fault codes relating to it.

[uzigon]

Nevermind, after a couple days I get DTCs. Seems like I will need to blank off and/or replace the valve solenoid.

[wheeler]

Nevermind, after a couple days I get DTCs. Seems like I will need to blank off and/or replace the valve solenoid.

Blanking off wont get rid of the fault codes. the MAF will detect that its not working.

[uzigon]

Is it not possible to use diagnostics software to have the computer "forget" about the EGR?

I have bigger problems now that the clutch on the EGS has gone and it has left me stranded up the country until I can figure out a solution.