At what position should the needle sit at when hot

12, o'clock when up to correct temp...  Pete

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2014 L405 Autobiography SDV8 4.4 Loire Blue Ebony interior
2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Parchment over Navy Interior. Sold
2012 L322 Autobiography 5.0 Supercharged Ipanema Sand, Jet Interior. Sold
2002 L322 Vogue 4.4 V8 Epson Green, Ivory over Aspen Interior (Fatty Offroader) Sold
-Click for Project Fatty off roader-

About 5 to 10 to recently, as it's got colder.
But then even in the summer, it never goes over 12 o'clock.

Beware that the needle position is not a direct feed from the coolant sensor: instead it is the ECU's interpretation of the value produced by the sensor.
My Td6 was showing normal - i.e. needle half way up the scale, but the coolant temperature when read digitally from the OBDII date stream was never exceeding 80ºC.
Consequently I changed the thermostat and now the coolant temperature is around 92 - 93ºC, but lo and behold the needle is in exactly the same position.
Funnily enough my fuel consumption has improved now that the engine is in its optimum operating window, and the heater is far more efficient.

All modern vehicles now have gauges that do what the maker thinks you need to know... Not sure on the TD6 but the M62 get's to normal at under 80 degrees and then doesn't move off normal until the temp gets above 115-120 deg a bit useless for measurement like an old gauge, they may as well just have a light...  Pete

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2014 L405 Autobiography SDV8 4.4 Loire Blue Ebony interior
2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Parchment over Navy Interior. Sold
2012 L322 Autobiography 5.0 Supercharged Ipanema Sand, Jet Interior. Sold
2002 L322 Vogue 4.4 V8 Epson Green, Ivory over Aspen Interior (Fatty Offroader) Sold
-Click for Project Fatty off roader-

Once warm mine sits squarely at 12 oclock but its not always been that way. When I first got the car the gauge was always on the low side, dropping lower when I was on a long run. After researching here and investigation I found the EGR thermostat was knackered, stuck open. Fitted a new one and now all good. Simple fix if thats your issue. This vid will give you an idea, not exactly the same, ours have a different hose fitting.
https://www.youtube.com/watch?v=P7VFfaXSSso 2007 TDV8 VSE
2003 TD6 gone.
2002 P38a gone
1999 P38a gone
1997 p38a gone
1993 VSE gone
1992 VSE gone
1966 Series 2a with V8 conversion gone

I can say with confidence that normal starts at 60 and goes over 100 degrees as I have a proper temp gauge on my ffrr too... so if your gauge isn't getting to the 12 o'clock position I would suspect that you thermostat is in the open all the time, or fubar mode

Oh and Pete not all modern cars suffer from an ecu temp gauge.. my other tractor the gauge goes up and down like a yoyo... unless there is an intermittent wiring fault  Yesterday I couldn't spell Engineer... Today I are one!
Inventor of the 'Guide-o-Matic automatic wheel alignment tool'
Former long term L322 owner, Up/Down graded to a Classic Tractor!

If that is where it sits after a run then I would say that it is a bit low on the temp.... However it could be the gauge... the needle might be in the wrong place..... I would suggest that plugging in a IID tool might be a very good idea, as you can see the temp that the ECU is seeing...not what it thinks you want to see.

Failing that then either a laser temp ray-gun thingy, adding an extra gauge or a trip to an indy, would help diagnose the problem... But if you don't already have one a IID tool will be the best investment.... it's a bit of a when you see the price, but trust me they are worth every penny  Yesterday I couldn't spell Engineer... Today I are one!
Inventor of the 'Guide-o-Matic automatic wheel alignment tool'
Former long term L322 owner, Up/Down graded to a Classic Tractor!

I will plug it into my launch what should it read in relation to the gauge

Well normal should be around 75 - 100 degrees centigrade, as long as your over 70 then I wouldn't worry, if it's below then I'd be looking at the EGR thermostat and then the engine thermostat... but the EGR one is way easier to get at  Yesterday I couldn't spell Engineer... Today I are one!
Inventor of the 'Guide-o-Matic automatic wheel alignment tool'
Former long term L322 owner, Up/Down graded to a Classic Tractor!

Yes but eBay don't have them listed

Search for item 11712247723 on eBay.

17 mpg
@ndf

I don't hang about