Overheating and A/C problems with the 2018 Audi A3 Diesel

Hi, it's a head thing. Had a similar experience with my 2015 Audi A5 last week. The thing was, it wasn't the speed sensor, but it turned out that the coolant was leaking from the radiator and not transferring enough cooling ability to the engine. That's why the air conditioning wasn't getting cold. It was definitely a serious problem that needed to be solved immediately in a workshop. The radiator defect was pretty hidden, so they had to take half the engine apart to find it and replace it. You should get a good mechanic to look at it, but in my experience it's usually due to a loss of coolant. Check to see if there's a puddle under your car, that would be a pretty sure sign. Hope that helps you!

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It's really annoying when you have problems like that, isn't it? I kind of went through that too, my old A3 was also a hot-headed diva. I hope you get to the bottom of it soon. Can I ask how much you ended up leaving with the mechanic for the whole thing? And have you had any more problems since then or was it finally over after that? Thank you!

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Hey, here I am again. So, after the mechanic took the A5 under the knife, the speed sensor of the engine fan was actually in the bucket. How good that I went to see the guy! It was then replaced and my wallet was lightened by €250. But since then, the grinder has been running like a charm again, without boiling up or the A/C bucking. So, I hope you have the same luck with your A3. If necessary, have the speed sensor checked! Keep cool, buddy!

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Thanks guys for all the helpful tips and your insights. Regarding your question, the problem ended up costing me around €260. The mechanic actually had to change the coolant. There was a crack in the radiator and the coolant was almost empty. After the radiator was replaced and the coolant refilled, the problem with the A/C was also solved. It now cools like the first day again and no more overheating. So, you were right, it was the coolant. To be on the safe side, I also had the speed sensor checked, but it was fine. Since then everything has been running perfectly, no further complications. Thanks again for your support! It was an expensive lesson, but at least I now know more about my A3. Stay healthy and have a safe journey!

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