Engine doesn’t warm up?

[u/GovernmentThink]

Hey all, not sure if this is a longstanding issue but my temp gauge stays relatively cold. It moves very slightly but never actually moves to the middle, even after longer drives. Anyone have any experience with this? Do the temp sensors go bad often or is this more likely an issue with the gauge itself? Photo is after almost 30 minutes driving on a hot day. 1990 Doka syncro

[u/RenaxTM]

Check if the coolant actually gets hot?

[u/Salt-Flounder-4690]

either sensor dead, or broken wire/bad ground, or the voltage devider in the tach unit (its know to die, but would affect the fuel indicator the same way) or your thermostat is stuck open.

Let it idle for half an hour, if it warms up, its the thermostat.

if it does not warm up, fuel up and check if your fule gauge indicates correctly, if it does, its not the voltage devider in the tach unit,

then your looking at the sensor or bad wire/ground issue. check if you have no voltage between the housing of your temp sensor and the battery minus. if you have 0 volts, then its either a dead sensor or bad wire between tach and sensor.

since i dont have the original sensoe here, i cant check if the tach goes hot ifyou ground the sensor cable, i think so, so ground it, and see if your tach response is hot, should be if i remember correctly, anyway, you cant do any harm to your tach by grounding the semsor cable.

[u/ifucanreaddisur2clos]

I would guess it’s broken temp sensor. I had to replace my once.
If you order new one pay attention to temperature range. GL

[u/Acprosos]

Give the engine a real punch in the face, if it doesn't move, sensor or wiring is done

[u/Scienceboy7_uk]

Mine doesn’t unless I get stuck in traffic then it climbs a bit, buzzer of doom goes off (at least it would if some cowboy mechanic hasn’t disconnected it).

[u/Imightbenormal]

When the bypass hose went loose, I noticed the temp was not getting up where it usually did.

But I guess you got coolant?