My primary fan operates on my '88 GTA but the guage goes really high before it kicks on. I have the digital dash.

The temp guage seems sit just above 190 normally. I have good circulation from the water and stat. Good pressure, no boil overs or anything. When I sit in traffic the temp gauge will climb to 1 or 2 positions before the red 260 area before the fan comes on.

It is really hard to tell what the exact temperature is by looking at this digital guage. It's possible that it is inaccurate.

I have replaced the coolant temperature sensor. Fan still comes on about the same time.

What I want to do is check the actual coolant temperature. I found a chart of resistance vs. temperature on the board in another thread. I pulled the wires from my coolant sensor while cold and measured the resistance between the 2 leads on the sensor and it matched the chart. Is this an accurate way to measure the temperature that my ECM is recieving?

Also, does the digital dash temp gauge use a engine temperature switch or what does it use to operate the guage? Where is it located on my GTA? I could change that as well.

Thanks in advance,
J

A couple more small problems to fix and I can get a little body work and paint job on this car and will be all restored.

 

According to my CTS the ECM is operating the fan correctly. The temp guage reads about right up to 190 deg. on my digital dash. After 190 the readings get worse and worse. The CTS tests out at about 220 deg. and the guage says 235-240. Is this normal for them to become more inaccurate as the temp rises?

Also, is the temperature switch or sending unit the same for a regular guage and the digital dash guage in a GTA? It might be worth replacing as I'm sure it's original as well.