1993 astra

[rich.]

hello chaps, a mate has inherited his mothers astra (petrol) & its a spotless car but the temp gauge always runs nearly in the red but hasnt boiled..the car has been checked several times but he is still a bit worried.. is i most likely the gauge is a bit over excited or a deeper problem?

[TerryG]

Does it go to red as soon as the car is started or does it slowly rise?
If it goes straight to the red then the sensor or gauge is dead, if it rises through use then the first thing to check is that it isn't actually overheating. a cheap laser thermometer from ebay would be handy tool to have for this job.
I wouldn't expect either part to be particularly expensive if they need replacing.

[rich.]

from what i understand it goes up slowly gets to near the red & stops there, in trafic the cooling fans go on & off.. i will try & find out more.

[JPB]

This could be a result of increased resistance by a glazed or corroded connection in the instrument panel's PCB. Once you've found out whether the sender is the right one for the gauge, take a meter to the board, checking - between the lead in to each via and its surrounding tracks - for anything above zero resistance with the meter on a >1KΩ scale (lower ranges can amplify inaccuracies caused by the meter). It's a Vauxhall so worst case scenario is that you need a board from a scrapped car. These are neither more nor less likely to suffer from this sort of problem than anything else, so there should be plenty of usable secondhand parts around.

[rich.]

oo that sounds testicle, i will pass it on! thanks john

[JPB]

No double decker bus, you're very defibrillator.

[rich.]

thanks john, since the op ive always walked like that

[JPB]

And there I was assuming that it was just because you iron your jeans in a funny way..