COOLANT GAUGE SENSOR REPLACEMENT

Special Thanks to Fred Frigo for the contribution of most of this information. It is guys like Fred that help keep our Saabs rolling along. Kudos to Fred!

During normal operation, after the car has been running for several minutes the temperature gauge should be at the midpoint between L and H, almost completely horizontal. My temperature gauge rose much less than expected, and over time seemed to barely rise above L. The operation of the heater was normal indicating that the thermostat was not faulty. Replacing the Engine Coolant Gauge Temperature Sensor solved the problem. When these sensors fail you may also see issues with the needle on the temperature gauge intermittently fluctuating wildly as well.

To replace the engine coolant temperature sensor, unlock the connector and unplug it as shown in the photo below. Then use a wrench to remove the sensor from the engine block. When the sensor is removed coolant will flow out, so it is a good idea to have the new sensor close by, so it can quickly be inserted into the hole where the old sensor is removed from. After the sensor is tightened, attach the cable and lock it into place