low coolant warning light question...

Upon initial start up with cold motor I am receiving a "check coolant level" warning light. I regularly check coolant level and have done so after the warning light...and it is right where it needs to be, between min and max. With the warning light, I am also getting a slow red flashing light on the temp gauge. The car runs at 175 degrees, or right in the middle, where it always has. The temp has never moved beyond the middle. I have scheduled an appointment, but it isn't until a week from now. My thoughts are that it may be a faulty coolant level sensor, but could it be something else...or is there something else I can check? I'd love to save myself a trip to the dealer. The dealer said all should be fine as long as coolant is topped off and there is no signs of over heating. Any insight would be appreciated. Lastly, my car has only 3k miles on a porsche warranted full rebuild. So the water pump, thermostat, all hoses, all fluids etc are brand new with only 3k miles. My car is a 08 Cayman S Sport w/39k miles.

Forgot to mention that after driving and engine up to temp, the warning light sometimes goes off, and sometimes stays on...it's quite sporadic. Also, if I turn off the engine, and restart, sometimes the warning will go away. It's quite bothersome....

Sounds like they left an air pocket after the rebuild. Not unusual. Check for posts on bleeding the cooling system. It's a good idea to remedy this sooner than later. An air pocket can mean that some parts of the engine/system aren't getting necessary cooling. Maybe they didn't open the heater core (temp to max hot) when they did their bleed. If they are anything like my dealer - they missed it all together.

The coolant reed sensor is accessible if you remove the passenger tire and heat shielding. Easy item to replace but kind of black magic with the twist to get it to stay.

^I have taken the car to the dealer 2 times for a coolant smell, and both times they did an overnight pressure test with no issues found. . They also said the system has been bled for air pockets...this is c why I'm getting so frustrated...and now the low coolant light that keeps coming on. So apparently something is up, but not yet resolved. I do appreciate the feedback!

BTW if you unplug the sensor and the issue "goes away" then you either have a faulty float in the coolant tank or ECU issues.

Thanks B8. Is the sensor located on the bottom of tge coolant tank?...or where should I look? Thanks

Yes, the coolant LEVEL sensor is bottom of the coolant tank. Past Audi owner hence the B8.

The temp sensor failed on my LE. One additional symptom I had that you don't mention is it would be hard starting when warm. Turns out that was because the sensor wasn't registering that the car was warm, so it would give extra gas at startup. Since it didn't need extra gas, it would flood. But the sensor that failed and I replaced was in the front of the engine. I had to remove the front engine cover. The most difficult part of the operation was figuring out how to remove the electrical plug w/o damaging it. The rest of the job only took about an hr. Here's a link from a prev post that has pics. http://www.planet-9.com/987-cayman-...xster-service-and-tech/60772-coolant-temperature-sensor-sender-replacement.html

I just remembered... About a month ago there was a 981 thread about a false overheat condition that turned out to be caused by a vacuum leak. Maybe with all that rebuild work there is a loose hose. Sounds like they're focusing on cooling issues and might of missed something as simple as that.

FWIW I don't think the 987.1 would have the vacuum leak issue. No vacuum controlled valves in the cooling system. At least that I'm aware of. With coolant smell and low level warnings with no apparent signs of overheating (how I hate having an idiot light masquerading as a gauge) have you checked the simple stuff? Remove the engine cover and made sure the blue pressure cap on the expansion tank is tight and not leaking? Usually there's a pink residue from dried coolant if it is. And the bleeder valve shouldn't normally be open. The wire tab should be laying down instead of flipped up. This is also on the expansion tank. You can check the level from the blue cap . If you do so all the usual cautions apply. Make sure the engines cool, remove slowly, etc. If you have it off make sure the o-ring in the cap isn't damaged. I believe there's an article on engine cover removal. I've seen a thread on bleeding. Think I've seen one on replacing the level sensor also. Few ideas to consider.

Would it be safe to drive my car with the warning light, or should I park it until my appointment? As I mentioned before, the dealer didn't seem too concerned as long as the coolant is topped off.

If you accept that there are no guarantees with a free, remote internet diagnosis I don't see a reason not to drive it as long as you have the coolant topped off and no indication of overheating. Not just on the gauge but the way it's running. That you can smell coolant makes me think you have a leak somewhere and maybe less coolant than it appears to be. Also makes me wonder about the dealers pressure check. It's not abnormal to have it gulp a qt or so when the system was drained even with a vacuum fill. Been a while but I sort of recall doing a double take and then getting a good light to tell for sure the first time I had the remote fill in the trunk open due to internal reflections and the way the tabs lay. Just be sure...

Update: I took the Cayman in for the warning light and coolant smell. Dealer diagnosed a leaking heater core hose. $19.00 part and coolant flush and all is 100%. Put on about 300 miles since having it fixed and no more smell or warning light.

Thanks for the update. Sounds like the cost to fix was cheap, especially by Porsche standards. Where was the heater core hose located? Under the dash? Eddie

In a miracle of maintainability the heater hoses are easy to get to under the hood near the battery .

Thanks Rob VN. Who'd a thunk it and good to know. Eddie

Fwiw, I ran an errand in my '10 BS Saturday, and the car ran fine. It was parked downhill for several hours in pretty cool weather (40's), and when my wife and I jumped in it later that evening to go to dinner, the warning light came on and the temp gauge was buried in the top/red area, even though the car was stone cold and we'd only gone around the block. Drove straight home and parked it. Next morning, started it up and got the same result, so checked the coolant level and could not see any coolant. I started the car later to check the coolant level and the code/error/warning light was gone. Moved it so it was flat but still no sign of coolant in the rear tank. Got some pre-mix, filled it, and the code/warning stayed off. Feel like I am lucky that the sensor error issues some previous posts mentioned don't seem to be the case for me. Looks like it simply got to the point where the sensor correctly indicated a low coolant level.