Birch works best.....

Or a good piece of hazel if you can find it.  There is nothing that can't be fixed with a hammer😜😜
FFRR 4.4 SDV8 Autobiography Santorini Black.
Fiat 500x 1.4 multiair Lounge 2015
2010 LR D4 Commercial 2.7 TDV6

Bit of an update.....

Dad tried esso diesel which helped a bit, and after I pointed out that we'd looked at most things and it's still smoking, it went to the main dealer.

£120 later and a replaced split hose, all is cured.

I said, and we posted here about split hoses, but this one could not easily be accessed from above, so dad didn't check that far.

 2011 Range Rover Vogue SE 4.4 TDV8

Previous cars :
2003 Range Rover Vogue TD6
1999 Discovery Td5 ES
1995 BMW M5 3.8 6 speed
1992 Range Rover 3.9 Efi Vogue
1992 BMW M5 3.8
1988 BMW 735i SE
1989 Ford Sierra XR4x4 2.9i
1981 Ford Fiesta Supersport

Glad it's all sorted now

Guess it was a boost hose then? FFRR MY06 facelift With TDV8 Alloys Zeros/ATR's
Mantec Sump Guard, Rigid Load liner, MY10 BT upgrade.

Dad said they said it was the inter cooler hose.

It's running much better apparently. He never noticed that it wasn't before. Must have degraded over time.

He said it was £30 for the actual hose...... 2011 Range Rover Vogue SE 4.4 TDV8

Previous cars :
2003 Range Rover Vogue TD6
1999 Discovery Td5 ES
1995 BMW M5 3.8 6 speed
1992 Range Rover 3.9 Efi Vogue
1992 BMW M5 3.8
1988 BMW 735i SE
1989 Ford Sierra XR4x4 2.9i
1981 Ford Fiesta Supersport