Temperature sensor and/or gauge problems??

When I start up my car in the morning and after the car is warmed up after 5 minutes or so, the temp gauge will at times not go up to the 1/3 mark and only up to about an 1/8 of the way up. At times it doesn’t even come up at all. During the times it doesn’t go up all the way, I will take a test light, hook up the positive to the + side of the battery terminal, and touch the test light to my temperature sensor on the motor. Then the temp gauge will pop up to the normal 1/2 way mark. Any thoughts, suggestions, theories toward what is going on here? Any help is greatly appreciated. TIA.


i would suggest checking the line, it sounds like a short. i don’t know how much a replacement line would cost, it might be easier to just hook up an aftermarket pod. you also might try resetting the ECU, but it sounds more like a short.

Thanks for your reply. When you mean short, do you mean that the wire may be bad somewhere and I should check that first?

Anyone else? TIA.

my dad’s car did that, and it was because the thermostat was screwed. Changed it, and itz all good.