Club 80-90 Forums

I know this has been asked many many times, but hey just for clarification.

I recently changed the gauge as the red light wasnt flashing for the self test. I thought its still moving so what the hell, It would sit just under the red light, then on a 200 mile trip it would creep just above then back down, All good, but didnt like the fact that it wasnt flashing. I bought a second hand one, plugged it in, flashing on startup then it would go out. Happy days. Now the problem is it doesnt even creep to quarter and usually sits just above the white box. When i put the air to cool creeps up to quarter maybe, then warm air back to just above white box. Going down a hill it goes into the white box.

Going on a road trip on Monday so will give it a good run out then, in the meantime is it something I should worry about or take it these gauges are different from one to the next.

I have this issue after changing from and early coolant system engine to a late style. My gauge worked fine before so I am assuming it isnt directly that. I am wandering if different gauges need different sensors, i.e. they change what Ohms read out as what?

To the OP
It doesn't matter really where it reads , VW say "normal" is anywhere between the two white markings , and frankly , wherever it's made it's new "normal" don't worry, only worry if it suddenly changes from that place !
Mine sits almost exactly as you describe , it always has done since I've owned the van . It will creep up in traffic , the fan cuts in about two needles widths over the red light

You could change the sender , it may or may not change it .

I'm sure the resistance of the wiring has as. I have to do with the reading as the actual sender , cleaning connections may change things

Smosh, early to late means you have gone from a engine earthed sender ( single wire ) to a double insulated sender , the resistances will be different between the early and late senders for this reason alone

Mocki wrote:To the OP
It doesn't matter really where it reads , VW say "normal" is anywhere between the two white markings , and frankly , wherever it's made it's new "normal" don't worry, only worry if it suddenly changes from that place !
Mine sits almost exactly as you describe , it always has done since I've owned the van . It will creep up in traffic , the fan cuts in about two needles widths over the red light

You could change the sender , it may or may not change it .

I'm sure the resistance of the wiring has as. I have to do with the reading as the actual sender , cleaning connections may change things

Smosh, early to late means you have gone from a engine earthed sender ( single wire ) to a double insulated sender , the resistances will be different between the early and late senders for this reason alone

Thanks for that Steve. Will leave as is for the time being

It might be the fact you have a great working cooling system.
Mine used to be always middle or slightly above. Had a major service, including coolant flush and change. The temp gauge now reads much cooler!

Mocki wrote:
Smosh, early to late means you have gone from a engine earthed sender ( single wire ) to a double insulated sender , the resistances will be different between the early and late senders for this reason alone

Yea, that's what thought, so the gauge will read wrong. Is there an easy way to correct this? Changing the gauges sound expensive/ messy!

Gauge reports resistance through sender. High resistance means low reading low resistance means high reading. No resistance means overheating.
So resistance at corroded connectors could cause low temp readings.