Davedex Posted September 30, 2014 Report Share Posted September 30, 2014 Can anyone help? My temp gauge works perfectly about 70% of the time but suddenly drops down to zero for no reason. After a short while it will come back up to the normal section again. Is it likely to be the sensor that sticks out of the side of the expansion vessel? Or is it likely to be something else located in a different part of the engine? Any help gratefully received. Quote Link to comment Share on other sites More sharing options...
Skezza Posted September 30, 2014 Report Share Posted September 30, 2014 It's the standard temp sensor. It gives off two readings, one to the ECU, one to the dash.Not a big deal, I drove around with no reading for about 3 years. Perhaps next time you're not busy buy a new temp gauge, no rush though. Quote Link to comment Share on other sites More sharing options...
danoid Posted September 30, 2014 Report Share Posted September 30, 2014 Increases MPG and efficency if you change it, as the engine can run richer if it think the car is cold Quote Link to comment Share on other sites More sharing options...
Skezza Posted September 30, 2014 Report Share Posted September 30, 2014 (edited) Increases MPG and efficency if you change it, as the engine can run richer if it think the car is coldI've already explained why this is completely wrong. A failed temperature sensor will lead to more than the car running rich. I would imagine it be stalling all over the place.Just get a OBD2 and plug in, you'll see the correct temperature reading in the ECU. The one to the dial is not linked to the one to the ECU. Edited September 30, 2014 by Skezza Quote Link to comment Share on other sites More sharing options...
danoid Posted September 30, 2014 Report Share Posted September 30, 2014 Thatd a good point, but if the sensor is faulty (both parts), it could be sending incorrect figures to the ECU aswell as the dash.I know ours was and got massive increase in MPG Quote Link to comment Share on other sites More sharing options...
Skezza Posted September 30, 2014 Report Share Posted September 30, 2014 Thatd a good point, but if the sensor is faulty (both parts), it could be sending incorrect figures to the ECU aswell as the dash.I know ours was and got massive increase in MPGThis is possible to be fair, but when I observed my own temp gauge via OBD2, it was clear that the reading to the ECU was correct.Still, it's an easy part to fix Quote Link to comment Share on other sites More sharing options...
malte Posted September 30, 2014 Report Share Posted September 30, 2014 (edited) I don't know how the quality is on the ebay-sensors, but might be worth trying. Oem is expensive, replaced mine a few weeks ago. Don't forget to buy a new o-ring as well. Edited September 30, 2014 by malte Quote Link to comment Share on other sites More sharing options...
Skezza Posted September 30, 2014 Report Share Posted September 30, 2014 Meh, worse that can happen is they fail quickly. Euro Car Parts does them pretty cheap mind. Quote Link to comment Share on other sites More sharing options...
Davedex Posted October 1, 2014 Author Report Share Posted October 1, 2014 Am I right in guessing that there are two types,? I guess I just need to take the old one off and get another one of them. Is there an easy way to tell before I take it off so that I can have the new one ready to put on when I go the job? Quote Link to comment Share on other sites More sharing options...
Skezza Posted October 1, 2014 Report Share Posted October 1, 2014 (edited) Am I right in guessing that there are two types,? I guess I just need to take the old one off and get another one of them. Is there an easy way to tell before I take it off so that I can have the new one ready to put on when I go the job?Two types of what? Your car has a single temperature sensor. It provides readings to both clocks and ECU. The clock feed often fails. You can check this using an OBD2 tool or a VCDS.when you decide to fix it (in my case when the coolant level sensor gummed up and started sticking) you buy the temp sensor from somewhere, ECP is usually good, and fit it.Enjoy a cold beer after. Edited October 1, 2014 by Skezza Quote Link to comment Share on other sites More sharing options...
malte Posted October 2, 2014 Report Share Posted October 2, 2014 Am I right in guessing that there are two types,? I guess I just need to take the old one off and get another one of them. Is there an easy way to tell before I take it off so that I can have the new one ready to put on when I go the job?Take a look here to get the oem part number : http://www.partscats.info/volkswagen/en/?i=cat_vag_models&brand=vw Quote Link to comment Share on other sites More sharing options...
Dblock Posted October 3, 2014 Report Share Posted October 3, 2014 I've already explained why this is completely wrong. A failed temperature sensor will lead to more than the car running rich. I would imagine it be stalling all over the place.Just get a OBD2 and plug in, you'll see the correct temperature reading in the ECU. The one to the dial is not linked to the one to the ECU.No Daniod is right. The sensor reverts to a low reading/nil reading when not working. So it will think the engine is constantly cold. That will not lead to stalling. But as said it had 2 signals. The one to the clocks isn't important. It's only if the one to the ecu fails will it do the failsafe above. Quote Link to comment Share on other sites More sharing options...
Skezza Posted October 3, 2014 Report Share Posted October 3, 2014 No Daniod is right. The sensor reverts to a low reading/nil reading when not working. So it will think the engine is constantly cold. That will not lead to stalling. But as said it had 2 signals. The one to the clocks isn't important. It's only if the one to the ecu fails will it do the failsafe above. Dblock, the clocks one tends to fail quite often on these. Until he gets it plugged in, he won't know if it has. However when it failed on mine, I plugged in and observed my car come up to operating temperature properly.I ran it like this for 3 years and the feed to the ECU never failed. As I said, I only changed it when the coolant level sensor failed. Quote Link to comment Share on other sites More sharing options...
Dblock Posted October 3, 2014 Report Share Posted October 3, 2014 That is true, but I'm saying if the whole sensor is shafted or the ecu signals is that's the problem. The one going to the clocks is just for show really. Quote Link to comment Share on other sites More sharing options...
Skezza Posted October 4, 2014 Report Share Posted October 4, 2014 (edited) That is true, but I'm saying if the whole sensor is shafted or the ecu signals is that's the problem. The one going to the clocks is just for show really.True. Won't know till it's plugged in. In my case, it wasn't an issue. This is why I genuinely believe the first thing EVERYONE should buy when owning their first car (or even if it isn't, just buy one!!) is a Bluetooth OBD2 dongle. Less than a tenner and could have answered this question in 30 seconds. Edited October 4, 2014 by Skezza 1 Quote Link to comment Share on other sites More sharing options...
Dblock Posted October 4, 2014 Report Share Posted October 4, 2014 True. Won't know till it's plugged in. In my case, it wasn't an issue. This is why I genuinely believe the first thing EVERYONE should buy when owning their first car (or even if it isn't, just buy one!!) is a Bluetooth OBD2 dongle. Less than a tenner and could have answered this question in 30 seconds.I know lol. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.