Help Help Help... Temp Gauge Issue!!!

[Member1115]

I have a problem and dont know what it could be. It has to do with my temp gauge. At times, when it wants to, it will mark whether the engine is Cold, Hot, or anywhere in between. However it doesnt do it very frequently. Mostly it just stays below cold. Up until now, for the past 6 months at least no major problems have occured. However though, I notice that only when the temp gauge is working, the cooling fans kick on (if they have to) when the car is not in motion and engine is running. If not, I could be in bumper to bumper traffic with a hot engine, and no cooling fans running... thats the scary part... not good!!!

Anyways, here is what I have done so far. Changed out the thermostat and checked fuses relating to "cooling" in the fuse boxes.

I am wondering if it could be a sensor, but not sure as to which one. It is my understanding that there are two coolant sensors. One attached to the thermostat housing, and the other, more towards the front, in between the heat shield and the distributor cap.

One of my first questions is which one of the two sensors control or drives the temperature gauge? And secondly, is there a way to test whether the actual sensor or connecting wires are working properly to better pin point the problem child?

And just a quick naive note on this... isnt it a fact that "mechanical" problems are the ones that tend to per say develop with time. Example being a clogged radiator may at first create a mild problem which would prolong the timeframe for the car to overheat, and within time as the situation worsens, the car would overheat within a shorter timeframe. Thus the problem has now "developed".

Now, an "electrical" problem in general has no development stage timeframe for the situation to worsen. It just immediately becomes a problem. Example being a light bulb, a fuse, a spark plug... once they "give out"... thats it, no time for problem to "develop" per say.

Being that the case, if my problem is a sensor or electrical situation, shouldnt my temp gauge needle just point blank never ever function again, and not come and go back to life when it wants to?

This is why I went to change the thermostat, since I thought it was a sticking thermostat kind of a problem... or "mechanical" per say.

To everyone, thanks in advance for your thoughts and input on this issue. I'll check back later on today, and continuously to see if anyone has questions that may lead to better diagnosing the problem.

[NAiL05]

Check your temp sensor thats prob whats messin up. The one on the t-stat is the fan switch if I remember and the other one is the one for your temp.

[Member1115]

Thanks for your help on this.

After a new sensor, thermostat, replacing spilled antifreeze a couple of times... it turns out the problem was corroaded wires. After the things I had done, and still no fix, I got desperate and just started tugging at wires here and there. I asked my chic to sit in the drivers seat with her eyes glued to the temp gauge to see if any movement of the needle while I wiggled the wires around back and forth... and behold!!! It worked. So now I just adjusted and tied up the wire loom in a position that seems to maintain running current on the wire to make the temp gauge work.

Thanks again for your help on this...!!!