Engine temp too hot warning light...please help!

Good morning, new Cayman S (60k miles, service records) owner...daily driver (about 14 miles a day), and LOVE IT! BUT.... yesterday on drive home, mostly freeway, very light stop and go traffic, I did have the ac on love (outside temp was maybe 75) the engine temp went from the usual 175 all the way to the right side and the red light came on along with the warning Engine temp too hot. I shut off, let cool and made it home. Here is what I’ve done so far.. No visual leaks Coolant level check and good Oil level check and good 2 radiators up front seem to be running Passenger side vent running and sucking air in Have hot air from heater and cool air from ac Q; does the drivers side vent also have a fan? How does the engine bay displace engine heat? I think I can feel hot air being pushed out through the rear area by tires ? What are me next steps? Thank you!

I'll let more capable minds deal with the gist your issue, but can confirm that the driver's side does not have a fan...only on the passenger side which draws additional air in when motion itself is insufficient or to cool down the engine after shut off - if needed. The driver's side vent directs air into the air filter box and on into your engine. Otherwise, there are underbody air scoops that also channel air to cool the engine.....although I've heard of these being damaged, I've never heard to them being blocked. Not saying it can't happen....btw....how did you check that your front radiators were working properly? Sorry I can't be of more help.....I'm mechanically challenged.

Here are 3 thoughts off the top of my head: 1) The thermostat may have frozen shut. Get the car running and once it warms up make sure you have hot coolant running into the radiators. 2) The temperature sensor may be faulty. 3) Pull the panel behind the seats and make sure everything looks ok with the water pump (belt good, shaft turning, no leaks, etc).

Thank you...you did help with confirming the side vents. I had seen other post where ppl said one is intake one is exit.. then I’ve read only 3 fans ..two up front and one side. Thamks again.

Thanks for the reply! I just did another test drive, about 30 mins. Got up to temp, rechecked fluids and oil and coolant levels good. Drove around, got up to temp (mine always stayed at 175), it went up to 180-195, then down, and then at idle will go back up again. A few things I noticed: I used my OBD reader to check temps (engine and coolant) both read higher then gauge. I’m wondering accuracy of both now. Another thing was at idle after 30 min drive, the temp gauge would jump around a bit. Suddenly up..then drop a bit...like it was unsure.. definitely not normal or what I have seen before. I’ll open up panel behind seats and have a look now.. thank you again, much appreciated!

How old is the water pump? It could be time to replace it if it is original to the car.

Not sure.. I bought used..no dealer service records I have indicate water pump was replaced. So maybe it’s time.. Opened up behind seats... I see no leaks, sensor looks intact/snug fit, belt tight, all pullies spinning (ac when activated), pass side vent fan working as well. Hmmmmmm... no fault codes either. But as I said temp gauge can jump around a bit.. Thanks for reply!

Methinks... 1. Check coolant mix...what color is it? 2. Unseat and reseat coolant filler cap 3. Check overflow tank cap in engine bay 4. Replace water pump (DIY) 5. Replace thermostat (DIY) My 89k mile 987.1CS runs between 185-205 consistently if you are checking via OBDII . Sent from my VS995 using Tapatalk

You might also pull the front bumper off (not difficult) and clean the debris out of your radiators.

Thanks for reply and list.. I did the first 3 so far.. I called a shop I’ve take several cars and they are squeezing me in on Fri.. part of my decision is when I bought the car I added a 3year “everything” covered insurance for repairs.. talking to him on the phone, he’s thinking faulty temp sensor then t-stat..

Cheers... I just had this recently done.. !

its good that you're using the OBD readers instead - many here have mentioned the inaccuracy of the dash reading in between "its getting hot here" and "oh oh". i would start with a full service/replace coolant, water pump or the fans/radiators.

OP, the car holds 6 gallons of coolant. With all that plumbing it is possible to get air pockets. I'm pretty sure there is a write-up in Articles on how to bleed the coolant. From memory, you open up the engine compartment and open the expansion tank cap. While running the car up you add coolant or just distilled water (remember with 6 gallons, a little extra water won't dilute much). Find the article since it tells exactly what level to fill the tank. Since you have no maintenance history and don't even know what brand coolant is in there (the Porsche stuff is expensive), it might be a good idea to flush and refill. Use a recommended brand for Porsche and keep some pre-mixed so you can top-up when the inevitable air-pocket works its way through the system. BTW, is your contract only for repairs or does it cover maintenance too. Different things.

If the gauge is jumping around that tells me it's likely the temperature sensor or the connection to same. FYI the coolant temp gauge on our cars is more like an idiot light than a gauge. Once the car comes up to temp, the gauge reads a steady 175 even as the actual temperature fluctuates around.

RSchwerer, first.. great photo.. gotta love Dangerfield! Thanks for the reply.. I have bled the system .. and all levels are correct. I did get a maintenance history but no where did it state a water pump replacement. I"m at 60k and it just had the service at Porsche . The added insurance i purchased was expensive but it does cover all repairs.. for 3 years.. engine failure, water pump, electrical.. all that stuff.. but does not cover things like worn tires , glass.. (but my standard auto insurance covers glass)..

Racergreg, the temp gauge has jumped around a little bit.. a few times.. like from 175 up to 200.. then suddenly back down. then maybe up. like it can't make up it's mind.. I checked connection and it seems snug.. having a new sensor put in tomorrow morning.. and it looked over. I learned about what you are talking about with it being and "idiot" gauge.. especially after I was checking temp with my obd reader.. and it was much higher then 175.. though not overheating with warning light.. after driving around at low speeds for 30-40 mins.. was confusing at first..

Oh, was that Dangerfield? I thought it was our future ex-president I guess I was thinking of this: AFA insurance, some consider the Porsche water pump as an expendable maintenance item and replace at ~45K miles. I should probably replace my avatar:

The temp gauge is not real. Its more like low, medium and HOT!!. My OBD reader tells me this. Getting hot at idle points to air flow, to me. Fan problem ?? Awesome that you are covered for the $$$ end of this. Good luck and report back.:cheers::cheers:

I learned this as well...after I read with my OBD ! All three fans are coming on, but today on the way to drop off at shop, I noticed that all fans were on after a short period, before the needle reached 175. I know even then they don’t normally kick on.. so hmmmm.. hoping to hear back from shop by afternoon... will update when I have info.

Update and result: Final result was the t-stat was bad. Although the coolant temp sensor showed it being ok, I also had them replace. Cayman running perfect again and needle staying at that familiar 175.. Thanks everyone for the replies and help.. Btw, I’m in the Seattle area and used Chris German Auto in Redmond.. great team and service. Dropped off at shop this am.. they just called to say all systems look great, operating correctly.. except... the t-stat and possibly the coolant temp sensor.. I'll update with final word and repair from shop when done today! Thanks again for all help everyone..