I have had this problem with my temp gauge for a while now. It is reading a lot higher than it really is. It's off by about 30*-40*. So finally I got a new temp sensor for the gauge and put it in. Now it's reading even hotter! It stabilizes and doesn't overheat, but lingers right below that redzone. The reason why I know it's not as hot as it says is because I took my car down to local rad shop and the guy had a temp gun that he would point at the thermostat housing and get a reading. Is that an accurate reading of my running temp? Also, the sensor is not in the original place (driver's side block between #1 and #3 plugs), but instead on the passenger side block between the #6 and #8 plugs. Could this area be hotter than what the temp gun was reading, hence the higher reading. Could the relocation of the sensor be a bad place for an accurate reading? Any suggestions or experiences with this problem would be HIGHLY appreciated. Thanks everyone.

 

Stock gauges IMO are not accurate at all. I have an 86 Iroc and the sensor on the passanger side is for the cooling fan.

 

So my best bet would be to get an aftermarket one then? I just have this qwerk about not knowing my temperature, call me crazy. Thanks.

 

The thermostat housing is the hottest point that the collant can be tested, so yes, that is a very accurate reading. And those laser guns are seldom wrong. I had the same problem last summer. I replaced the coolant, hoses, stat, temp sesor, the whole nine yards...but the problem was the gauge itself. FOr some unknown the reason, the gauges in our cars after a few years tend to become useless. Some people have good luck with them, and most, like ourselves, get screwed. You can replace the gauge with an OE gauge, but you'll probably setting yourself up for more trouble later.
I would go to autozone and get the triple gauge setup that has the oil pressure, temp, and not sure what the other is. Your oil pressure gauge has a tendancy to be inaccurate as well so I would go ahead and take care of it now instead of later. If you really want to get fancy, you could get some of those pillar gauges.

 

check your water in the radiator. I had the same problem and i found out it was bone dry. Hope this helps!

 

Lol, good idea, sometimes you over look the easy stuff. Check the coolant level and if the rad cap is old, replace it. Oddly, sometimes an old rad cap that won't properly seal can cause some problems.

 

Believe me, EVERYTHING is checked and working efficiently. New 170* thermostat, new coolant, hoses are semi-new, water pump is new, temp sensor is brand new, and I just did a throttle body bypass. Even my oil pressure gauge is reading abnormally high, so I definitely just think it's the gauge. Oh yeah, and the fan motor is brand new and blowing well. I'm going to get the pillar gauges off of Jeg's. I was just wondering what to do with the POS stock gauges once I get the new ones. I'm not going to like having those gauges just sitting there doing nothing. It would be cool to put like a TV screen in there or something . Thanks for the input!

 

TV Screen huh? You going Knight Rider on us? Lol, I'm sure you can come up with somehting to do with them.