Dual Temperature Sensor help

[bigslippy]

Hi guys , I have a 2003 A4 1.9 tdi quattro, temp gauge hasn't worked for a couple of years and I had heard that if the temp
sensor isn't working , the ECU still thinks the engine is running cold and uses more fuel?

Is this the case as round town driving I get mid to high 30's , when I go on a journey I get mid 40's.... I wouldve thought 50+ would be easily achievable.

However , I've now discovered the part I need is called a dual temp sender .... does mean that 1 part tells the temp gauge what the temp is and the other part tells the ECU?

Hope this makes sense to somebody

Any thoughts/wisdom welcomed

 

[marktdisport]

To be honest after a few people on here with 1.9 Q say they only get mid 30's and there's a few fwd only doing mid to high 30's.. My fwd comes in as average around 42-45 mpg but if I do 550 miles then 400-410 will be dual Carriageway to work @ around 65-70 mph...on a very long journey it will creap to a near 50 driven carefully.. The temp sensor will work in a few ways but they all do.. Should just be a simple change over

 

[Greeny233]

Just get your temp gauge fixed, usually only the thermostat or coolant temp sensor.

 

[pauldazzle]

Temp sensor failure is one of the most common failures on VAG cars.
Yes the CTS has 2 outputs 1 to the gauge & 1 to the ECU. If the ECU is getting incorrect reading from the CTS it won't fuel correctly. Make sure you get a genuine VAG replacement (£25ish) Aftermarket CTS's are notorious for failing.