Coolant / Temperature gauge help

[hd_andy]

Hi All,

After some help please. GTI 2.0 8V

I had an issue with an airlock in the cooling system, all sorted now but its got me a bit paranoid about the gauge.

I have never seen it rise over halfway and now I am looking to test it.

The book of lies tells me that the sender is basically a variable resistor and as the temperature rises the resistance drops - hence unplugging the wire and grounding it will make the gauge read hot, i have tried this and nothing, from the book of lies it would appear to be the two wires closest to the head in the four way plug on the plastic flange going into the front of the head.

Also the oil temp on the mfa will obviously relate to water temp, so what are people reading on the oil temp at normal water temp?

Thanks in advance

Andy

[hd_andy]

Just another thought, the fan cuts in and out ok when hot - so another question, what are people reading on the temp gauge when the fan cuts in / out??

I am considering the risky strategy of unplugging the fan so I can see the temp rise further than the halfway mark.  Don't really want to try this though for obvious reasons!

[leegt5]

Once its up to temperature it should stay on the halfway mark !! The fan will come in and out and it will still sit on the halfway mark until you switch it off....... Your car is normal !! The oil temp is normally different to the coolant temp !!

[Wayne]

Once its up to temperature it should stay on the halfway mark !! The fan will come in and out and it will still sit on the halfway mark until you switch it off....... Your car is normal !! The oil temp is normally different to the coolant temp !!

+1 it is normal.

[andc1]

yep mine does the same, stays on half and fan cuts on and off

[Christo77]

Hi.. if i can add to andy's post...
I've just replaced the coolant and thermostat in my 8v, i suspected something was not right as my water temp seemed to operate only around quarter way on the guage.. Now the the gauge moves quite quickly from cold to the middle, and you chaps are right, according to the owners handbook normal running temp should be halfway on the gauge, so i'm all well pleased with that..but also that my oil temp reading when full running temperature reached was previously about 82, now it's 96/98..I guess that would make sense but if any of you chaps could confirm that?   Thanks
I think the coolant had never been changed..all that came out was kinda just brown water, not good!

[Wayne]

Hi.. if i can add to andy's post...
I've just replaced the coolant and thermostat in my 8v, i suspected something was not right as my water temp seemed to operate only around quarter way on the guage.. Now the the gauge moves quite quickly from cold to the middle, and you chaps are right, according to the owners handbook normal running temp should be halfway on the gauge, so i'm all well pleased with that..but also that my oil temp reading when full running temperature reached was previously about 82, now it's 96/98..I guess that would make sense but if any of you chaps could confirm that?   Thanks
I think the coolant had never been changed..all that came out was kinda just brown water, not good!

96 / 98 is ok, from memory mine was a little lower but it will not hurt.

[Christo77]

Ok yep, thanks for that