2.0T Quattro - Engine coolant over 100 degrees

[RedexElmo]

Hello all,

I've recently purchased a 2006 Audi A4 DTM with the BUL engine code on 83k. I bought an OBD adapter to keep an eye on temps.

Since using the adapter with Torque, I've noticed that quite often the coolant temperature will exceed 100 degrees Celsius, whilst the coolant guage on the dash shows 90.
Is this expected? I'm surprised that the guage on the dash doesn't read the sensor data accurately.

Heaters still seem to be working okay. When I checked the coolant level it was overfilled so I drained some but Torque still see temperatures exceeding 100 degrees.

The previous owner said the timing belt and water pump had been replaced by the owner before him but had no proof. Is there an easy way to see if this is true?

On a side note, the engine isles between 725 and 750 (I'm sure it was idling slightly higher before I noticed the temp issue). Could this be related?

Many thanks!!

 

[RedexElmo]

Here's a picture of the car

 

[LawrenceH]

Temperature gauges having a dead zone in the middle is pretty normal. Saves people panicking when it moves up a fraction in hot weather.

That said, over 100C in this weather does seem hot. Is it stable once it’s heated up or does it go up/down a lot?

Check rad isn’t blocked up before you go spending loads of money on it, could be something silly like a plastic bag stuck across in inside the bumper.

 

[KLBC]

Here's a picture of the car

Car looks great pal wheels look spot on! Is the RS4 grille standard with DTM A4s?