Running cold

My TD4 2005 is running cold 1/3 on the gauge ..... if I make it work it just reaches 1/2 on the gauge .... but will come back to 1/3 very quickly once cruising ... .. Have changed the thermostat ..... And have just ordered a temp sensor ..... If this does not work where to then .... It was running at 1/2 on gauge before and no problem with warming up ... It is a bit rough on the cold start up and a bit of white smoke out of exhaust .... I have had the vehicle for two years and just love my freelander .... Maybe the new thermostat has a problem I hope not because its a nightmare to change .....

mines been like this since the cold winter, seems fine now, runs a little colder than I remember, but nothing untoward.

wouldn't worry too much.