Some people install a separate coolant temp sensor. I just use an UltraGauge because I like the exact reading from the ECU instead of the vague stock gauge. I guess it just depends on how much modification you want to do.

I would like to add oil pressure one day though at which time I might get add an extra coolant temp sensor.

 

Not overkill at all, probably more of a necessity.I will be installing both oil pressure and coolant temp on pillar one of these days.

 

I'm now confused by the terms sensor and sender. Same thing? Stock DII only has one?

To confirm, the ECU tells the cluster temp gauge what to display? This is the programming problem that makes the needle stay still until it's actually boiling?

So there is no way to stuff new gauge parts into the existing cluster using the ECU feed. I would need the 2nd sensor/sender.

 

most after market setup also go in the upper hose, were the stock unit is in the lower intake. so installing a separate gauge is much more beneficial than just piggybacking off the ecu signal. imho

 

For general purposes a sensor/sender are the same. I believe technically a sensor is used to send information to an ECU and the sender is capable of sending directly to a gauge.

And yes the ECU tells the cluster temp gauge what to display, its just at what temp the needle moves is a problem. If you were using an UltraGauge to monitor the reading you could see swings from 180-220 and the needle would never move.

 

I think the gauge step motor was intentionally set to not fluctuate. Most likely to keep owners from freaking out, because these engines do fluctuate 15-25 degrees. The needle would be moving constantly.