tdi b8 2.0

Hi Guys, I have a B8 8K3 a4 allroad that is smoking sometimes. The smoke is white (oil) and only seems to happen after coasting. according to other forum posts it may be a bad PCV valve. How do I test if the PCV is working correctly and if the oil is coming from there? The pipe from the...

Help had been appreciated! Applies to Audi A4 B8 TDI 2009. The fuel pump under the car, pump number 2 (not the one in the tank), had oxidized the cables so that it did not run, which resulted in no fuel to the engine. Took a while to find the fault but now that it is fixed the car does not start...