I have a 2003 A4 1.8T Quattro, and sometimes while I am driving the coolant gauge will go from normal position to cold then back to normal. Sometimes it will stay at the cold position for a minute then back to normal. I would say it does this once a day. Does anyone know what it might be? I can only think of maybe a loose connector or a short in the wire.

And where is the sending unit located on the block so I can check it?

TIA
Deryl

P.S. If anyone has a picture or drawing of its location that would be great as well...

***UPDATE!!***

I vagged the car today and these were the faults I found.

19497 - Powertrain Databus Implausible Engine Temp. Message from Inst. Panel
P3041 - 004 - No Signal/Communication - Intermittent

00604 - Potentiometer Positioning Motor for Air Flow Flap (G113)
30-10 - Open or Short to B+ - Intermittent

01039 - Coolant Temperature Sensor (G2)
30-10 - Open or Short to B+ - Intermittent

00562 - Sensor for Oil Level/Temperature (G266)
30-00 - Open or Short to B+

What do I need to do? Please help me. I am new to Audi and need some assistance.

TIA

 

I would start by replacing the coolant temp sensor. Milliion writups on that subject.