1990 Running temperature question

[Guest Rustbelt]

The temperature gauge on my 1990 commonly sits at the '12' o'clock position during city and highway driving.

Found myself stuck on the expressway recently due to construction delays, and the gauge slowly began to climb up.

The furthest it reached was "2" o'clock, (one 'click' before red) fluctuating between 1 and 2 o'clock as we inched forward. When the road opened up to normal speeds, it quickly returned to it's normal '12 o'clock' position.

I had the cooling system flushed several wks prior to this happening, as well as the power steering, since this is a new to me, first Reatta. 

I've attached a picture for reference, taken before a cold start so you can see the 'clock' positions.....

 

Can anyone translate the 'clock positions' on my gauge into actual temperature readings and advise me if further action should be taken?

Thanks

 

[89RedDarkGrey]

Please go HERE, for your answers, and it's advisable to follow the upgrade directions. Your car will thank you

[Barney Eaton]

Allow me to go a little deeper into the fan operation.....the fan(s) are controlled by the engine temperature input to the engine control module (ECM)

The first stage of fan operation is the fan on the engine side of the radiator, as temp rises or if you turn on the A/C the fan in front of the radiator kicks on.

At this stage the front and rear fan is running at half speed as the circuit has them wired in series.

Then when you are in traffic etc that causes the temp to rise further, the ECM switches some relays and each fan get 12V and they run at full speed.

Your temp gage is showing a little higher than most people see in traffic so maybe you need to verify they are kicking into the final stage.

Since your screen name is "rustbelt" I'm thinking you do not live in the south and need to do anything out of the ordinary except verify that the fans are operating properly.

First check that both fans are working.

Then you could run 12v to either fan to get a feeling of what full speed looks and sounds like.

Below is the schematic for your fans.

[padgett]

I have a 180F thermostat and fans programmed to come on LO at 185 and HI at 189. The halfway bar can be anything from 180 to 200F so really need to look at ED04 to know what the temperature sender is reading (is in centigrade). For me I have found that keeping the engine a bit cooler makes everything under the hood (belts, hoses, battery, etc) last longer and AC output is improved.

[89RedDarkGrey]

I have never seen one in person, and there's no mention on ROJ of it- does the '90-'91 Reatta IPC have the same capabilities as the '88-'89 CRT for bidirectional control (override) of systems? I can't see a way for all that info to be displayed in the tiny ODO area.

[padgett]

Similar. Selection is in the HVAC display and data is on IPC