Sad night for a first time Porsche owner here. Received my CPO 2017 C4 GTS Cab roughly 4 weeks ago. Driven under 500 miles. Received an overheating warning message tonight after a 10 minute drive in normal conditions to get gas. “Engine over temp. Park vehicle to cool down.” At the same time it sounded like a massive jet taking off all around/in front of me in the cabin; after researching it sounds like those were some fans outside the engine bay. Interestingly, the engine fans were not on during ignition or while turned off. I let the car sit for 30 and turned it back on. Within 2-3 minutes the dial went all the way back up to 250 with the warning light. After researching here, I checked the coolant level and sure enough the red ball was located at “Min”. This resulted in me calling Porsche roadside assistance to have it towed. I’m really at a loss how I could have been sold a car roughly one month ago with a CPO checklist indicating “Pass” for coolant levels only to see that after not even 500 miles and maybe 2 full weeks of driving, the level is at “Min” and a warning light tripped. Hoping to learn more once the dealer gets into it tomorrow and praying no damage to the engine occurred.

 

Sorry to hear this and very weird to Happen to a modern car. Your dealer will get it sorted.

 

Well, it could be the water pump or another issue like leaking hose, not sure if it was a CPO miss or not. Sounds like the engine was completely dry. Anyway things do break out of nowhere on all cars.

Bummer though and I’d be more concerned if any engine damage occurred because it over heated. I had a BMW (back in the day, an e30), same thing happened. After cool down, I started it and seconds later it went hot.

After a hose was repaired, 6-months later the head warped and needed a rebuild. Likely caused by the over heating incident. Anyway good luck. Please report back on what went wrong.

 

99% chance of water pump failure. It is quite common on the 991.2. Plenty of threads about it.

 

Likely water pump leak leading to flooding of changeover valves.

Car likely did not actually overheat—the indicators just a safety measure.

Will need to have water pump, coolant pump, changeover valves, changeover block, vacuum lines replaced.

Should be covered under warranty.

 

And we got extended warranty on it now for 10 years!

 

Unfortunately this isn't a terribly uncommon story and there isn't really a good . The coolant levels were likely in spec at the time of the check, something failed shortly afterwards, and here you are now. That's how cars work.

You're CPO, so they'll fix it at no cost to you other than some time in a loaner.

As an aside, I'm not sure the GTS is in the same bucket as GT cars, but for us lesser 991.2s we have a pretty dumb coolant temperature gauge. The real temperature is available, but it flattens it out to 194F during anything within operating range. See my thread here for more details.

Welcome to the 911 life.

 

Any update from dealer??

 

My bet is this ^^. Same thing happened to me. Could be that pump was changed before you bought but they did not change the lines and the block. Fans spinning within an inch of their lives. Take a breath, I think (hope) you'll be ok.

 

it could also be as simple as coolant level just slightly lower than normal, it triggers the same warning and the "fake" temp gauge in instrument cluster goes to MAX

 

My C4GTS has the same coolant gauge reading as the other non GT cars.

 

Confirmed water pump failure. Said not even attempting to fix. Ordered parts from a few states over and will take roughly a week to get it back. Bummed this happened within a few weeks of ownership but glad it is CPO. Worried about resale value now that this will be in the history.

 

I would make sure they check the changeover valves for function. Again, the water pump can leak internally and foul these changeover valves, producing the symptoms you’ve described.

Replacing water pump only might not do it.

 

Really appreciate the tip!! Will ask them tomorrow.

 

It'll help resale value, if anything.