Where is the needle supposed to be?

Michael Mattix

SCCoA Member
Where is the temperature gauge needle supposed to be when traveling at interstate speeds on a 95 5sp? Mine (I thought) used to be dead center between the left vertical white line and the "n". But, now I noticed this last weekend when I was traveling on the interstate that the needle was resting on the "n" the last half of my trip and I just had a flush and fill and the thermostat changed last month! Doesn't the fan turn on when the needle gets to the "m" or something? Maybe this isn't a very accurate device to measure when trouble might be rearing it's ugly head, but I would sure like to know what kind of reading everyone else is getting on their cars! Thanks ahead of time!
 
There are a lot of SC's out here that have the temp gauge sitting at "M" under normal operating conditions. I would generally say not to worry about it too much except that this is not the normal condition for your car. It could be that when the "flush and fill" was done, the little cap (bolt) on the stem next to the thermostat was not opened during the refill. This is the coolant system air release. If this wasn't opened during the fill, there could be air trapped in the system causing the increase in temp.
This could also be related to the wrong thermostat being installed (if you replaced it during the servicing).
The cooling fan cuts off at speeds above 40mph (I believe) because the system uses airflow from outside.
 
If you were running blow the "N", then you likely had a 180 thermostat in the car to begin with. Most SC's run above the "O". Anything below the "O" should be considered cool. I would watch for consistancy. If the gauge fluctuates, the I would suspect air in the system.
 
LJGriggs said:
There are a lot of SC's out here that have the temp gauge sitting at "M" under normal operating conditions.

My Cougar is like that. It annoyed me at first since Fords were well known for placing the TEMP needle about 1/4 of the way up the gauge over many years. From the mid Sixties to the late Eighties as a rule.

THIS car tends to run the needle about the last leg of the "M" at 70mph with the AC on. I initially thought it was hot when I got the car but a cross check with the ECT sensor found the thing was right on the 195* thermostat (hey I'm trying for mileage here :D )

But what's worse is that the gauge is erratic. 90% of the time it works like described but other times it reads even higher, sometimes to the point of causing the Check Gauges light to illuminate. This was distressing until I figured out that the cooling fan wasn't on so the thing obviously wasn't really hot. Again a cross-check proved it was the gauge.

Then it will very rarely read lower, about where the "O" is. This isn't real common for this car.

AC on will result in a one needle-width rise in the temp gauge reading immediately, which says its electrical. I haven't bothered to look for a reason. I just know it does it and compensate mentally.

IMO, if you really want to know what the engine temp is install an aftermarket gauge.

edit:fixed my typing dyslexia
 
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need;e

my needle always chills under the letters....below N and the rest...if it touches the letters...i think of it as running hot...cause im paranoid it will blow a head or something....im not sure if this is stock thermo or not...but i have had this car for 5 years and all i have done is change the coolant every 6 months...this summer planning to change to a 180 tstat and water wetter. my prob is that the gauge sometimes...just goes up then back to normal which i dont like, and i have replaced the sending unit sensor. i dont know if thats bad.
 
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