Hi CK
Yes that is quite possible. 
​If things do not seem to be working as you expect the first thing to do is check your installation. 
1.turn on your system and check that power is going to your gauge.
2. check that the negative is flowing freely back to the battery. A good negative is more important than a good positive to a gauge.
3. check that the signal wire is connected to the (correct)  pole of your sensor.
For a temperature gauge in a cold system the gauge should be reading zero. If your gauge is reading any value disconnect the signal wire from the sensor. It should now be reading zero. If not your gauge is faulty.
4. disconnect the signal wire from the sensor and touch the wire on to the body of the sensor (not the pole the brass part of the sensor). The gauge should jump up to max temp. If this happened your gauge and signal wire are good if not:
​4.1 touch the signal wire on the NEGATIVE pole of your battery. if the gauge jumps up to maximum  you have a engine earthing problem to fix. If the gauge did not move then you have a signal wire problem to fix.
5 if the gauge and signal wire are working correctly then you have a sensor issue.

​I hope that this helps.

Block connector is a simple and effective way of connecting your panel to its wiring harness. It has the advantage of only needing simple tools to work with it. It is also great when you only want to connect or disconnect one wire at a time.
Robust and long lasting, not water proof but water gets out as easy as it gets in so great when under cover.
​Main disadvantage is it takes time to connect or disconnect the whole thing.

This is the one that I choose. Snap lock connectors give you the convenience of being able to connect up a number of wires at once and if the wiring gets wet it will dry out again once conditions allow.
The main disadvantage is that you need a special crimping tool to attach the wires correctly. Though it is possible to use small pliers to do the job. 

Superseal connectors can be the best choice for connecting up the wiring on your boat. if they are put together correctly using the correct tools they do a magnificent job. However there are a number of things to think about:

1. Water and electricity  or electrical components do not mix - ever. If your wiring is getting wet these connectors will not cure the problem in the long term.
2. They are quite complex. Getting all the parts together in the correct order and locked can be a real puzzle.
3. You do need the correct crimping tool to connect the wires correctly. You crimp the wire and the little rubber seal at the same time in one action. This seals the seal itself to the wire and puts the seal in the correct position to seal into the block.
4. You must get the connector the correct way up when you insert it into the block or it will not lock.
5. You must lock the anti-pullback devices correctly or the wires WILL - 100% WILL work their way lose over time and break the connection. But the connector will look as though it is done up.
6. The big bad lost at sea problem is - They are waterproof. If water gets in it will stay in - it can not get out. This will provide the ideal conditions for corrosion but also provide a very good conductor. So from the outside they look great and work well until you pull them apart and all the metal parts have rusted away.
   

​So superseal can be the best solution to boat wiring - but check them every now and then on dry days. Also even though its a waterproof connector try to avoid them getting wet.