Schizo temperature gauge

craig2105 · Jun 11, 2009

OK, so after buying the car I noticed the temperature guage pinged up to max after stopping at the motorway services on the way home. No sign of overheating - levels OK and the fans cut in and out happily.When the ignition is off, the pointer stays up at max but a tap on the instrument cluster glass will persuade it to pop back down to rest again. Then it pinged straight back up to max again with the ignition on.

I changed the temperature sender this morning in the hope of an easy fix, but it hasn't exactly gone to plan. The guage still pinged to max when I turned the ignition on again. On a drive out to pick up some other bits from OPC Reading, the guage suddenly started working again, but then the temerature rose rapidly, then settled back to half way, then started pinging up and down erraticly, then pinged up to max and stayed there.

A friend with a 968 said he had a similar problem with his, ultimately cured by swapping out the gauge for a new one. Is that the next best thing to do - there's a dash pod on ebay for reasonable money ending later today, so if the advice is to try that next, I'll bid tonight? I trust it's just a case of pulling the pod apart and removing the guage from the donor?

Advice please chaps!

Thanks, Craig

Riverside · Jun 11, 2009

I had similar symptoms with my oil pressure gauge a couple of years ago, changed the sensor but discovered the problem was a short in the engine bay. Wiring problems are really hard to diagnose if it isn't obvious physical damage so a new sensor & gauge will help you to find the problem by substitution. Might not fix the problem but still worth doing.

DavidL · Jun 11, 2009

I had this - try taking the dash out and the instrument pod - its not that hard, have a look at Clarks garage.
Behind each gauge there is an oval flat metal piece held in with a 7mm? bolt.
Take the bolt off and pull the oval piece out - it has 2 1cm prongs attached to it. Take some wet and dry to the prongs even if they look nice and shiny. Refit it all.
When the pod is out it is worth cleaning anything else that looks in the slightest dirty or tarnished.
If tapping the dash fixes it chances are the dodgy connection is in the instrument pod.

Hope that solves it for you.
David