Hi guys, well the title says it all but I will add that the engine does run cold most of the time and the temp gauge is erratic, not sure if these things are related or not as this is the first Audi I have ever owned! thanks in advance

 

replace your temp sending unit ot temp sensor, same part different names. It is usually on the right side behind bank 1 in a pipe against the firewall.

Order the sensor, o-ring and retaining clip.