Citroen C4 B7 2.0l HDi oil leak

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Citroen C4 B7 2.0l HDi oil leak

Post by hitmeh »

Hi all,

First time poster here, a few days ago I’ve noticed a part of engine covered in oil, however my knowledge of cars ends and being able to replace brake pads, so could anyone tell me what the highlighted part is and where the oil could be coming from?
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Re: Citroen C4 B7 2.0l HDi oil leak

Post by PeteC8 »

Horrendous trying to locate leaks around that engine! My first line of attack is to thoroughly clean around the whole area, I use petrol and a 1/2" painting brush and aerosol brake cleaner. Once all is dry, drive it and then determine!

For the record, that cylindrical unit is the EGR actuator. It has a diaphragm inside which actuates a spring loaded arm via that rod, opening an auxilliary air valve in the inlet casting. It is worked by vacuum via the right angled pipe. No oil in that part! The square sectioned section is shroud for various air pipes from memory.

Hope that helps, Pete

(Now in return help me fix my Auto gearbox fault!!)
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Re: Citroen C4 B7 2.0l HDi oil leak

Post by PaulC5 »

Rather than the egr actuator, is it not the doser valve (egr by-pass) actuator. We had a 1.6 hdi C4 and the doser valve on that leaked oil out of its body joint and it dripped on to the alternator, maybe the oil was from the turbo, it was a 2008 C4 and the doser valve body was plastic. The leak was fixed with a new doser unit but the car was sold before any checks were made to see if the turbo was losing a lot of oil. ... tbsvAAAAAA ... gJXgvD_BwE