I had a similar problem on my Peugeot 405.
I've dismounted the gauges panel, and found out that
one of the connections to the temperature gauge is done
by a washer and nut.
I've replaced the washer (it was a little bent), sprayed some
electronics cleaning fluid around, and that fixed the problem.
> The temperature guage on my Peugeot Partner van flickers from maximum
> to just above minimum all the time that the engine is running, or when
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> Many thanks for any suggestions
> Steve