trshot

Hello, I Just joined this forum hoping for insight on two codes I have on a 2018 Q7 2.0, they are P2024 & P2025. My scanner describes them as P2025, a temperature sensor for tank ventilation implausible signal and P2024, fuel vapor temperature sensor circuit. I mentioned the P2025 first as it's a hard code and sets quickly. I can't find any sensor related to this and the dealer shows nothing as well. I'm wondering if it's possibly the leak detection pump. Any help is greatly appreciated, thanks.

singcarl

I have the same code on my 2018 sq5, did you ever figure this out?

Handydoctor

Did you figure it out? Mine has a p2026. Still trying to troubleshoot. Thank you.

Handydoctor

Did you figure it out? Mine has a p2026. Still trying to troubleshoot. Thank you.

singcarl

so I was waiting to reply to see if the issue was corrected and I believe it’s now safe to say I figured it out on mine. I started leaning towards the PCV intake tubing. I saw a video on YouTube on how to test it by removing it and blowing into one end to see if it would hold pressure or not. Well it’s is a pain in the butt to remove, and as I removed the clips (the push in on both sides and pull) one of the hoses basically came apart in my hand. I wasn’t sure if it was me man handling it that caused it or if it had been compromised beforehand. Now I wouldn’t know if that hose had held pressure in its entirety but I was able to test it from the broken part to the diaphragm and it tested good. Well I already had to replace it because it was broken, but I suspected it was leaking where it broke before hand. 157.00 later from Audi I had the new part and got it swapped out. Immediately the light on the dash went off and I have not had any issues since. It’s been 2 tanks of fuel now. Never would I have gone that long before. And usually the code would pop when fuel levels were low after a start stop or if I fueled up. No issues on any of those examples now. The part number for my vehicle was 06M-129-041 and it is called an “intake manifold”

Handydoctor

Good job for fixing your problem. Why did you lean towards the PCV tube? This is a gasoline vapor code and PCV mostly deals with oil vapor. Again good job for fixing it but if you don't mind, please tell us your thought process. Thank you. BTW, is sq5 3.0t? Mine is a 2t and I don't know whether this part would be the same.

I didn't fix my problem. My code is p2026, low voltage on vapor temperature. When the connector was removed from the vapor detection module, the code becomes p2024, vapor temperature sensor circuit, and I thought this must be it. Well, with a new module, it still p2026. Oh well...

If anyone has any idea, please help. Thank you. I will try looking at the PCV too.
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singcarl

yes mine is an SQ5 with the 3.0t. I believe yours is significantly different. This is oil vapors but I believe on the 3.0t the hose assembly also deals with EGR. There are multiple hoses in the assembly going to other places that I believe would allow the leak. I had leaned this direction after watching a few videos online and learning it was a common problem on these.

Handydoctor

Thank you. Do you still have links to those videos?

Handydoctor

OK, I looked into a manual for 2.0T. It appears that the N80 valve connects onto the oil separator with a hose. So indeed, on the 2.0T, evap and pcv are connected. I for some time feel that the oil separator has too much oil inside. That part is transparent...Something I didn't know before but now I know. Some people in fact replace the oil separator on the 2.0T every 50k to avoid losing the rear main seal. Anyhow, that's probably something I am going to look into first. Maybe there's a leak there and maybe it's time to replace the separator. Only 38k miles right now but again, I have suspected it for a while.

As always, if anybody has anything, please help. Thank you.

irontmp

P2024 evap fuel vapor temperature sensor circuit 2014 q5 2.0 turbo, I changed leak detector pump and fuel pump , I checked wiring and fuses and the code active/static it can’t be erased, it comes back up . Any ideas what could it be? Where is this sensor located?