temperature gauge stuck hot
 

97 V6 4.2
I installed instrument cluster from 98 Expedition to gain tachometer. Direct fit. One problem is the temperature hits hot as soon as engine is started. Easy to fix?

Can individual gauges be replaced?

Thanks.

The sensor connects to the dash electronics.
The gage connects at a different point in the electronics.
Look on both sides for the issue.
The gage is a voltmeter. The electronics and sensor are a vairable resistance to limit the voltage the meter sees in relation to the temperature.
A pegged meter indicates it's seeing max voltage instead of what the sensor circuit feeds to it.
Good luck.

I wonder if he installed a sensor from a 98 Expedition if that would send the right reading to the gauge? I think that is what I would try first.

did one truck have a temp gauge and the other an idiot light that comes on when "hot".. one sensor is varaiable risistor, the other is an on-off switch.

Thank for the replies. I gave up on this 98 Expedition cluster and am going to add an aftermarket tach to the original cluster.

According to the wiring diagram, the sensor input goes to a microchip which in turn feeds the gauge. Not much diagnosis to do. All I could do was to see if an electrolytic capacitor leaked. But there was none. Individual gauges cannot be replaced.

When the pickup is started, temp stays at the bottom. About a minute or two later, it suddenly pegs to max. Turns engine off and back on. Pegs to max immediately. Wait a day. Returns to bottom. Other gauges work just fine. By the way, temp warning light remains off.

I found a post here someone successfully installed a cluster from Expedition to his F150. His goal was the same, to get the tachometer. I am sure it's the gauge problem, not interchangeabiblity.

Tach is the only difference between the two clusters. Both have a temp warning light and a temp gauge.

Thanks again. I am putting my old gauge cluster back. Anyhow, the Expedition odometer is 50,000 miles higher than mine.

I went to the jy to return the instrument cluster for store credit. I went through the Ford rows one last time and found another 98 Expedition. Removed instrument cluster. Wow, so new. The original must have gone bad.

Direct fit. Everything works.
Thanks.