by any chance does it go off after a few days of dry weather if so front wheels off and take off the plastic inner arches 2 screws and a few plastic pull off plastic pins top rear on body work theres a wire connector from wheels sensor clean it check and solder wires if needed clean the ring with the humps in just behind the front wheel bearing / disk this is abs wheel sensor this has stopped mine coming on
The blue smoke is from burning engine oil. Could be worn Turbo spindle bearing and seals causing oil to be pumped into the exhaust. Worn piston rings general engine wear. Worst case is dieseling on your lubricating oil when the turbo spindle is worn and lubricating oil is being pumped into the compressed air scroll and into the combustion chamber. Eventually all of the lubricating oil is consumed as fuel and the engine siezes.
White smoke could be unburnt diesel or coolant. Could be a damaged fuel injector, fault with injector timing or DPF (if you have one). Knowing how most people don't know how to look after a VM diesel engine, I reckon it is probably a coolant problem, cracked head or failed head gasket.
A VM turbo diesel needs at least 30 seconds of idling after starting to ensure good oil pressure is on the turbo spindle bearings before driving. It also needs at least a minute of idling before switching off to allow the turbo to slow down and cool down with oil pressure on the spindle bearing. If the car has just done a high speed journey or been driven hard to get high exhaust gas temperatures (EGT) it will need longer idling to cool down, 3 minutes or more. Today you won't find any manufacturer say this is necessary, but if you do this from new with any turbo diesel engine you are likely to have fewer problems with cracked heads, failed gaskets, failed turbos or dieseling on your lubricating oil.
here is a link that has all years and models in PDF format, just pick the one for your car and download/save I got mine from here http://oskin.ru/pub/chrysler-dodge/manuals/Service%20Manuals/
try the connectors front from the sensor wire to main car wireing its in wheel arch top forward just behind plastic arch body a few pull off fixers and two screws clean and refit has maded mine work for some time
