DS3 ‘pump’ noise from rear - AdBlue?

[gwltabb]

I’ve had DS 3 HDI 2016 with for about 4 months. Car has be spot on but I’ve just noticed after driving for 5-10 minutes and then pulling up and sitting in idle, I can hear what sounds like a pump coming from the rear, it comes on about 6-7 times with about 10 seconds inbetween. It sounds exactly like the rear wiper motor but obviously it is not that.

I can only assume this is the AdBlue pump. I’m not sure if this has always been there or not but now I’ve heard it you can’t miss it. No warning lights. Is this likely to be the cause and if so is this normal? Seems odd to pump so many times. Doesn’t seem to do it driving for longer periods after the first time. Hoping it’s not on the way out.

[GiveMeABreak]

Pop your VIN up so I can check if you have one. Please post your VIN in full without spaces - it will be automatically masked from public view after submitting your post & will only be visible to staff.

[gwltabb]

To check if I’ve got AdBlue pump? I’ve got a tank full of it under the spare wheel of that helps. Happy to post the VIN if it will definitely help but I’m certain I’ve got the AdBlue system.

[GiveMeABreak]

Ok, so if you are certain then the noise you can hear when the engine stops is the adblue pump working in reverse to suck back the fluid into the tank. It does this to help reduce crystallisation of the fluid in the UREA supply pipe.

[gwltabb]

Thanks. Is that normal to go on for like 6-7 times? It doesn’t do it just once. Also this is at idle, not when turning the engine off.

[GiveMeABreak]

Yes it can take 5-15 seconds generally. Put it this way, I parked up, switched ignition off and went to the tailgate, opened it when mine was doing the same, got the shopping out and shut the boot and it stopped shortly afterwards.

[gwltabb]

Thanks so much, very reassuring!