Coolant temp sensor is a likely suspect. I have the following values for an '84 2.3, and would bet they are the same for '85.
at 20C 2200-2800 ohms
at 80C 290-370 ohms
at 100C 140-220 ohms
The slope is close to linear, but not quite.
Measure between the sensor pin and ground, and be sure you distinguish between the temp sensor for the KE system and the temp sensor for the IP gage.