Engine smoke and knocking.
AUDI A1 Sportback (8XA, 8XF)

Audi A1 1.6 tdi.

Driving at highway speeds (70ish) and begun to slow. Depressed clutch, rev count went to max and cloud of white/grey smoke from exhaust. Puddle of cold orangy water by drivers side. Pushed to hangar and car would then turn over. When running loud knock is heard from engine bay and smoke from engine and exhaust. 

Car had not exceeded 4000 rpm, was warm when driving began, and temp gauge was at 90 after coolant dumped.

Found out later (not my car) that the car had been losing coolant with no puddle in the morning. Engine was partially rebuilt in September 22 as it had blown up previously. No sign of oil leaking from oil pan suspect possibly broken camshaft and seals or waterpump.

Would broken camshaft and seals/water pump plus possibly headgasket cause a fairly loud knock and smoke from both engine and exhaust.