[urq] temperature sender confusion

[John Terreric]

Hello all,

this is my first post here, even though I have been enjoying reading you all for some time.

I have a 84 UrQ which has been well restored (engine new, suspension news, new paint) and an upgraded ECU (I suspect it was from a 4000 but I did not get any details).

Previous owners have also installed a classic 3 gauge VDO unit. 2 of the 3 gauges work (oil pressure and battery) but not the coolant temperature. Again no assurance those senders are legit.

My mechanic is confused as there are already 3 temperature senders on the engine and one is connected to the gauge but it doesn't do anything to it. It would simply not budge at any temperature. But if he puts the lead to ground the gauge goes full scale - so there is a valid wiring and gauge functionality it seems.

So does it come from a wrong sender, i.e. with the wrong resistance? Or the right sender but the wrong gauge?

Thank you for your help in advance,

Eric
84 UrQ