Need advice: Temperature gauge malfunction in my Audi A8L 3.0 quattro

I have seen the coolant temperature gauge oscillating between the middle and quarter position.

BHPian storme'd recently shared this with other enthusiasts.

Guys, need some advice. My current drive is an Audi A8L quattro 3.0. Have been having quite an issue free experience with the car, however post getting it serviced from Halfords last week, I have seen the coolant temperature gauge oscillating between the middle and quarter position. It used to be fixed at the mid spot earlier but now the needle keeps moving. Thankfully it's not going beyond the half level so have not faced any issues.

• Can this be due to something that happened during servicing?
• What could be the culprit?
• If it is the coolant temperature sensor, can I do a diy after buying it off Amazon?

Any advice will be helpful.

Thanks.

Here's what BHPian Maverick5490 had to say on the matter:

Does the temperature gauge fluctuate right from start up or once the engine is in operating temperature? Most likely its the sensor that may have failed causing the erratic display.

Here's what BHPian ajmat had to say on the matter:

First - Halfords may be best routine services of popular cars as opposed to a sophisticated Audi.

It could be a faulty temp sensor. Are you getting any error messages, fuel consumption issues? Some of the early 2000 VAG cars had defective sensors. My Skoda RS has this issue. For £15, I got a new sensor posted to me. Replaced it and it was sweet as a nut. This sits at the bottom of the block. Considering your v8, you could get lost!

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