Overheating Astra: Coolant Mystery Needs Expert Eyes

Hey there! Had the exact same issue with my 2013 Vauxhall Insignia 2.0 CDTI last winter. The symptoms you're describing ring a bell, I faced identical problems. Took it to my local Vauxhall specialist last month. Turned out the PTC (Electric auxiliary heater) was indeed faulty, and it was causing the engine to overheat. The coolant loss was actually connected to this issue. They had to replace the entire PTC unit and some damaged wiring. It's not a minor fix, took them about 4-5 hours to complete the job. The tricky part was accessing the heater unit, which is buried pretty deep in the engine bay. But once fixed, all the symptoms disappeared completely, no more warning lights, normal engine temp, and coolant level stays where it should. It's definitely something you want to get sorted soon though, as continuous overheating can lead to more serious engine damage. I'd suggest going to a certified Vauxhall specialist rather than a general garage, these heaters can be quite specific to handle.

Thanks for sharing your experience! That's really helpful to know. Quick question, do you remember roughly how much you ended up paying for the whole repair? Also, has everything been running smoothly since the fix, or have you noticed any other quirks pop up? I'm trying to get an idea of what I might be in for with my Astra.

Hey again! Yes, absolutely, since you asked, I ended up paying 350.00 € for the whole repair job on my Insignia. And I'm happy to report that everything's been running like a dream since then! The PTC heater issue was definitely what was causing all the trouble, and once they fixed it, all those annoying symptoms completely disappeared. The engine's running at normal temperature now, no more warning lights flashing at me, and best of all, I haven't had to top up the coolant even once since the repair. Such a relief after dealing with those constant coolant refills before! I've put about 5,000 km on the clock since the fix, and honestly, the car feels better than ever. No new issues have popped up, and it's actually running more efficiently now, I guess that's what happens when everything's working as it should! Trust me, it was worth every penny to get it sorted by a proper Vauxhall specialist. Sure beats dealing with an overheating engine and those constant warning lights, right?

Thanks a lot for all that info! Just wanted to update you, I took your advice and got my Astra checked out at a Vauxhall specialist yesterday. You were spot on about the PTC heater! Mine ended up costing a bit more, around 400.00 €, guess prices have gone up since you had yours done. The mechanic was actually really decent, showed me exactly what was wrong and explained everything. Got it all sorted in about 6 hours. Took a bit longer than yours because they found some corroded wiring that needed fixing too. Drove it home today and what a difference! No more warning lights, engine temp's perfect, and the coolant's staying exactly where it should be. Feel like I've got a different car! Really appreciate you sharing your experience, helped me avoid getting ripped off at my old mechanic's place. Sometimes it pays to ask around, eh? Thanks again!