Temperature Sensor problem?

**noone** · 16-07-2013, 07:14 PM

Nothing wrong with being fresh, I'm still very knowledgeless despite my efforts.

**Capoeirista** · 16-07-2013, 11:00 PM

Thanks noone. All a learning process for me I guess. I've read heaps of your posts and you seem to know quite a lot.

**louis19** · 01-10-2014, 06:41 AM

Did you end up finding the problem? I have the exact same issue, can get it to 90c, turn it off and even if I turn it Back on instantly it returns to 0c. Also don't hear the SAI anymore on cold start ups. All coolant pipes are warm and no fault lights are coming up.

Any ideas?

Originally Posted by Capoeirista

Hoping you can help me out. I've noticed that on cold starts my SAI doesn't kick in. Normally I can hear the SAI and then it turns off after a minute or so after starting, but now I don't hear it at all.

I've also noticed that when I turn the car on again (after driving and engine is warm), the temperature gauge resets back to 0. It then takes about 5 minutes to go back to normal running temperature (1/2 on gauge).

Could the above be a fault with the temperature sensor or is there an issue with the thermostat?

I don't want to have to go to the VW dealer and then have them rip me off if it is just as simple as changing the temp. sensor.

Thanks

**h100vw** · 01-10-2014, 09:41 AM

The SAI doesn't have to run every start, although they often come on on the first start of the day. Even with mine removed and coded out, I can hear the relay click pretty often.

Gavin

**louis19** · 01-10-2014, 09:57 AM

Originally Posted by h100vw

The SAI doesn't have to run every start, although they often come on on the first start of the day. Even with mine removed and coded out, I can hear the relay click pretty often.

Gavin

Thanks Gav, any explanation for the temp gauge resetting to zero and then slowly moving back up to 90c everytime I turn the car on even once the cars warm?

Edit, I have made a video of what's happening too: Gti Polo Problem: Gti Polo Problem - YouTube

Any help is appreciated

**h100vw** · 01-10-2014, 10:09 AM

Originally Posted by louis19

Thanks Gav, any explanation for the temp gauge resetting to zero and then slowly moving back up to 90c everytime I turn the car on even once the cars warm?

Edit, I have made a video of what's happening too: Gti Polo Problem: Gti Polo Problem - YouTube

Any help is appreciated

Can't explain that.

**ForceFed** · 01-10-2014, 10:28 AM

Same thing happens with my Polo gti. After driving a while and turn the car off and turn it on shortly after temp is at zero and then goes back to normal after a few minutes of driving and I have a brand new temp sensor.

**louis19** · 01-10-2014, 11:18 AM

Originally Posted by h100vw

Can't explain that.

If you can't then no one will be able to haha!

Originally Posted by ForceFed

Same thing happens with my Polo gti. After driving a while and turn the car off and turn it on shortly after temp is at zero and then goes back to normal after a few minutes of driving and I have a brand new temp sensor.

It's a weird one because you would think a new temp sensor would solve it with the mentality that the old one obviously is detecting temperature incorrectly when its restarted, thinking it's cold when it's really at 90c. However your not the first person who has replaced the CTS and had the problem continue.

Anyone else resolved the issue?

**rgvlee** · 01-10-2014, 11:55 AM

Tried to put an obd scanner on to see the temp reading as per the ecu? ECT is the obd code. To me that would rule out the temp sensor and push the issue back to the gauge itself.

**louis19** · 01-10-2014, 12:45 PM

Originally Posted by rgvlee

Tried to put an obd scanner on to see the temp reading as per the ecu? ECT is the obd code. To me that would rule out the temp sensor and push the issue back to the gauge itself.

No, I haven't. Is this something beyond what a VAG scan can detect?