Jumpy Oil Temperature Gauge

[Mark Elder]

On long trips (seems to need a couple of hundred miles before it starts happening!) my oil temp gauge starts to go bananas. It jumps instantly up to max (just above the red area) stays for a few seconds then drops back down to where it should be.

Occasionally it only jumps up to a "hot but not red hot" position.

It is definitely a gauge problem (rather than the sensor) because if I tap the gauge it drops back down to the correct position.

I'm assuming a dry solder joint somewhere inside the gauge. Anyone else seen this/know which joint it is likely to be?

 

[gm997_1]

Maybe a dodgy earth to the gauge, Mark?

On my 968 exactly the same thing happened as you describe and on that all the gauges are earthed through the earth connection to the instrument cluster, so it may well be exactly the same principle used on the 993.

In whihch case putting an independent earth wire to the metal back of your oil temp gauge could solve it. Certainly worked for me and very simple to try / fix.

Hope that helps.

Graeme

 

[D Ward]

Most likely a dry soldered joint as you suggested.
its normally the four large round pins that are pushed through the circuit board in to metal clips and solder in place, bit hard to describe but once you get the back off your gauge you will see them.
run some new solder onto them and your gauge should be good as new, worked for mine