Now the needle on my temp sensor normaly sticks dead centre once the car has warmed up.

However, today on the way to work I noticed that it went slightly to the right. Not much, but renough to see black between the centre line and the needle. It didn't get any higher or indeed any lower, it just stayed stationary.

Seemed a bit odd that it would stay there without any reason. I checked the coolant and couldn't spot anything odd, but obviously after 40miles the engine was a bit hot to start messing with.

If the temp remained constant, but the needle was in a slightly different place should I be worried?

How many miles has the car done.

Possibly the water pump has got some slight damage to it and isn't pumping quite as well or possible the thermostat isn't opening quite so far. Of course it could also be the sensor too.

Personally I'd keep an eye on it for a little while and watch. Obviously if it starts going up pull over and call somebody out. Failing that Get it checked out.

2000 slx tdi with 55k on the clock.

I'll see what it does tonight and report back. I've got a mate with VAG-COM so if it does persist I can get it checked out fairly easily.

does it do it when the engine is cold or only when you've been drving for a while??

also the fan switch might be duff, stopping the cooling fan from coming on.

There could be a load of reasons as indicated above. Keep an eye on it though, I had that, but soon shot right up closely followed by limp mode and white smoke out of the exhaust. It was the water pump blades that had gone, had the head checked and new gasket and pump and cam belt for good wallet killing measure.

It's been perfectly normal for the past couple of days, touch wood.