Hi folks.

Has anyone any idea what is causing this white deposit under the bonnet.
I've checked for any water leaks but found nothing.
Or, is it from above when the car is wet or washed, etc.

Cheers. Les. A Cheshire expat in France.
2015 RRS HSE 3.0 SDV6
2015 Aston Martin Vanquish
2010 Jaguar XFR Le Mans

Mines the same, I think it's just caused by hard water deposit's when washing the car, never tried it but white vinergar is supposed to help remove them.

Cheers
Col

Mines the same too

Thanks chaps.
The missus has a load of white vinegar so I might nick a bit.

Cheers. Les. A Cheshire expat in France.
2015 RRS HSE 3.0 SDV6
2015 Aston Martin Vanquish
2010 Jaguar XFR Le Mans

Me too Its a free extra Land Rover give you. A hard brush removes it, but it retur ns Range Rover Sport (gone): Mercedes S63 AMG Coupe: 992 Porsche Carrera 4S: Range Rover Fifty P400e

I'll have a chat with our son in the UK, he's into detailing so might know of a cure.  A Cheshire expat in France.
2015 RRS HSE 3.0 SDV6
2015 Aston Martin Vanquish
2010 Jaguar XFR Le Mans

Looks like salt which will stick to the insulation as the water dries out. If you live near the sea there's plenty in the atmosphere, damp mornings, warm engine are ideal conditions to create a build up.
A good soak in soft water should dissolve it.

If you think its from washing, I would strongly advise you get a domestic softener fitted, one of the best things you can do to extend the life of anything in your house in contact with hot water. Kettle, Iron, Dishwasher, Washing machine, taps, shower heads etc. Also soft water wont leave white streaks when rinsing the car.

Its easy to tell which automatic car washers have softeners fitted and which do not. RRS HSE Dynamic SDV6 2014

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I get the same but near the window washers i put it down to the fluid in washer tank when sprayed on window Love command drive position
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I was getting quite a heavy build up around the windscreen washer jet, put some aerospace locking wire round the jet/pipe connection which cured the problem