Porsche 996 Overheating? CTS Could Be Your Culprit!

Hey there! I have some experience working on cars. I actually faced a similar issue with my 2007 Porsche Cayman S. The symptoms were exactly like yours, overheating and check engine light. Turned out it was indeed a faulty sensor connection. Took it to my local Porsche specialist and they found a loose cable connection at the temperature sensor plug. The fix was pretty straightforward, they repaired the connection and everything went back to normal. Cost me around 95€ total. What's your exact mileage and have you noticed any coolant leaks? Also, does the temperature gauge show consistent readings or does it fluctuate? This info would help me share more relevant details from my experience. Just curious, have you had any other cooling system work done recently?

Hey, thanks for sharing your experience! My mileage is at 101592 km, and I just had a service last month where they checked the cooling system but found no leaks. I've noticed the temperature gauge has been acting a bit weird lately, it jumps around sometimes, especially during city driving. No visible coolant leaks that I can spot, but I'm really hoping it's just a sensor issue like yours was. That repair cost sounds way better than what I was fearing! Did your mechanic mention any other potential issues to watch out for while they were fixing yours?

Hey again! Thanks for the follow-up info about your 996. Yeah, that fluctuating temperature gauge definitely sounds familiar, mine did the exact same thing before I got it fixed. With your mileage being pretty similar to what mine was (I was at around 98000 km when I had the issue), I'm even more convinced it could be the same problem. Actually, while my mechanic was fixing the sensor connection, he did point out a couple of things to keep an eye on. He mentioned that on these Porsches, the water pump can sometimes start showing signs of wear around this mileage. In my case, the impeller was still in good shape, but he suggested keeping an ear out for any unusual whining sounds from that area. One thing I learned from my experience, even after fixing the sensor, I started doing regular cooling system flushes every 2 years. Just helps prevent any future issues, you know? Been running smooth for about 40k km since then. By the way, since you mentioned city driving, does your problem seem worse in stop-and-go traffic? Mine definitely was, and that was another clue that pointed to the sensor rather than something more serious. Keep me posted on what you find out! These cars are pretty solid once you sort out these little quirks.

Thanks so much for all the detailed info! Yeah, you're absolutely right, the temperature fluctuations are definitely worse in stop-and-go traffic. It's actually a relief to hear that your experience was so similar to mine. I'm going to schedule an appointment with my mechanic tomorrow and specifically ask them to check the sensor connections first. Really appreciate the heads-up about the water pump too. I'll have them take a look at that while they're at it, just to be on the safe side. And that's a great tip about the regular cooling system flushes, I'll definitely add that to my maintenance schedule. You've honestly made me feel a lot better about this whole situation. I was worried it might be something major, but now I'm pretty hopeful it's just the sensor like in your case. I'll update the forum once I get it sorted out. Thanks again for taking the time to share your experience!