Now that I know his actual surname a friend found this for me.
From the 1935 copy of Who's Who.
Coke,Col.Jacynth d'Ewes Fitz-Ercald, CMG 1918, CVO 1924, CBE 1927, late RASC; Chief Constable of West Suffolk since 1932; b 1879; m Elizabeth d.of late Albert Waller, of Shannon Grove, Banagher, Ireland; one s. two d. Served South Africa War, 1899 - 1902 (despatches, Queen's medal and 3 clasps, Kings medal and 1 clasp); European War, 1914-18 (despatches, CMG, Legion of Honour) Commander of the Order of the SAviour; retired pay, 1919; Chief Constable of the West Riding of Yorkshire 1919-20; Chief of the British Police Mission to the Greek Govt.,1929-31; His Majesty's Lieutenant for the City of London. Address: Thurston, Suffolk, Clubs: Junior United Service; West Suffolk County.
So now I know where he was in 1901.
Also Thurston is only about 8 miles from Walsham le Willows where the garage is that owned the car next. Quite possible that he sold the car to them direct without any intervening owners.
He certainly sounds like "quite a chap".