Overheating Corsa: Thermostat Issues & Repair Costs?

Hey there! I had a similar issue with my 2018 Vauxhall Astra (got some experience working with cars). The symptoms were pretty much identical to what you're describing. Turned out it wasn't the thermostat, it was actually damage to the wiring harness that was causing wonky readings and making the engine overheat. Took it to my regular workshop, and they had to replace some damaged wiring. The whole thing cost me around 170€. It's been running perfectly since then. What's the mileage on your Corsa? Also, did you notice any other electrical issues before this started happening? This info would help me share more relevant details from my experience.

Thanks for sharing that! Yeah, mine's at 172028 KM and just had its service last month. That's interesting about the wiring harness, I haven't noticed any other electrical issues, but I'll definitely keep that in mind. Did your mechanic spot the wiring problem right away, or did they have to dig deeper? I'm hoping it's something similarly straightforward and not too expensive to fix. Really appreciate the heads up about this!

Hey again! Yeah, with my Astra, it wasn't immediately obvious, the mechanics actually thought it was the thermostat at first too. They had to do some proper diagnostic work before they found the wiring issue. It was kind of hidden away near the coolant sensor area. The thing is, at around 170k km (mine was at 165k when it happened), these kinds of electrical gremlins start popping up. Since you haven't noticed any other electrical issues, that's actually a good sign! In my case, I'd had some occasional flickering with the dashboard lights before the overheating started. The fact that you just had a service done might be worth mentioning to your mechanic, sometimes these issues can start showing up after regular maintenance if something got knocked loose or wasn't reconnected properly. Not saying that's what happened, but worth checking out. Keep us posted on what they find! I'm curious to know if it turns out to be similar to what I experienced with my Astra. These Vauxhall engines are pretty solid overall, so hopefully it's nothing major.

Thanks so much for all that detailed info! That's really helpful to know about the diagnostic process and how it wasn't obvious at first. I'll definitely mention the recent service to my mechanic and ask them to check the wiring around the coolant sensor area. I've booked it in for tomorrow morning, so fingers crossed it's something relatively simple like what you experienced. I'll update the thread once I find out what's causing the issue. Really appreciate you taking the time to share your experience, it's given me a much better idea of what to expect!