Cooling System Temperature Gauge - Failure Indicator

[AceOfAces]

Hi everyone!

I'm glad I found this forum, seems like there's a nice group of Porsche enthusiasts here!

I bought an 2005 Carerra S several weeks ago and have been getting acquainted with her, especially getting use to the 6speed manual transmission. I took her out earlier for a spin and stalled at a stop light. Immediately after that my red light indicator for my Cooling System Temperature Gauge came on and the "Failure Indicator" text is on the display. Being my first Porsche, I'm in quite the panic so I hurried home to have a look at it. I open the engine compartment to check the water coolant levels and it is just over the minimum line.

I went online do do some research and the conclusions I've come up with are:

- possible engine overheating (though its quite cold here 9 degree celcius, and I drove her for no more than 10 minutes)

- a sensor defecting/and or wire/solenoid wear

- might need more coolant though she seems to have enough

This is where I need some advice, I'm planning to test this out in the following ways:

1) Tomorrow when the engines cooled down, I'll start her up again and see if I still get that error on the gauge

2) If that fails, take her to my dealer and get them to reset the computer via the Durametric device

3) If that fails, take it to the authorized Porsche Dealership and get them to check it out

Please do advise if there is anything else I can do or something I've missed out on that I can try. Thanks in advance everyone! :notworthy:

P.S. Just a quick little bit, when I bought her the engine light was on, but the dealer told me it'd go away after a few drives since she was sitting in the garage most of the time. After a few drives the engine light did in fact go away. It seems like the indicators on the Porsche 997.1 are very sensitive, which has me hopeful maybe this "Failure Indicator" would go away after it cools down.

[samuel.mercer]

Hi there,

My C2S MY2006 has had the same fault for around three years now and after changing the temperature sensor and numerous other visits to the dealership including a coolant change the indicator still goes on when it's wet or the temperature is less than around 20C.

If it's the same fault as mine then it's a non-fault, the temperature is fine it's just the reading of the temperature that doesn't work sometimes.

However I would get it checked out as for you it may be an indicator of a more serious problem, especially if you had the check engine light on when you bought it. For what it's worth I've never heard of the advice to drive the car until it goes away...

Here's the thread on my issue...

http://www.renntech.org/forums/topic/31192-failure-indicator/

Good luck,

Sam

[AceOfAces]

Thanks for the reply and pointing me to your original post Sam!

Checking this morning the "Indicator Failure" display is still there. I can see from the other post there are a few diagrams with where the temperature sensor is located. I wanted to know if you were able to get to it or was it in too small a space to have a tinker at. The cost of the part shouldn't be that expensive, but the labor cost can be ridiculous! Perhaps I'm in the wrong line of work as well!

If I had to take an educated guess at what the issue is, I think the temperature sensor is ajared. When stalling there was quite a lug forward perhaps enough to ajar the sensor.

I think I may have to bite the dust and bring it to the dealership as this may be something more than that, but we'll see what else I can check before that happens. It also doesn't help that the weather is all of a sudden shifting to winter now, so its hard to see if the 9C average is what is causing the issue as well.

Thanks again for the advice Sam, I now have a few other options I can look at first!

[AceOfAces]

An update:

I drove around a bit tonight and interestingly enough the temperature gauge error display disappeared as soon as the car warmed up (roughly 5 minutes of driving). I noticed as the oil temperature rose (farthest left indicator on the dash) was when the error display cleared. I'm starting to think I have what Sam had, or is this some sort of feature in the 997.1? It seems like the sensors are pretty sensitive, but I think I'll have it checked out next week or so to be on the absolute safe side. I'll keep updating if there is something I can learn from the mechanics about this.

[samuel.mercer]

Wow, it looks like you have the same problem that I do, even down to the thing rectifying itself when the engine gets warm. For me if there is a traffic jam and the air/parts around the engine warm up then the problem always goes away without exception but will re-manifest iteslf one the traffic clears and the airflow around the engine cools down again.

Although I am sorry to hear that you have this wonderful feature too, it's nice to hear of someone else who has it as I've never heard of any other owner having this issue. If you get anywhere finding a solution or you want me to test something on my car to help the investigation please let me know.

Sam

[AceOfAces]

Update:

Ever since I had this problem and it went away, its never come back, I suspect the computer just went sideways and fixed itself in the course of a few days later.

Yesterday I went to my mechanic and had a routine oil/oil filter/drain plug change as well as a full scan and checkup for my 997.1. They couldn't find anything error codes out of the ordinary, aside from a couple of engine misfire codes. Aside from that, a near future water pump/rear brake pad replacement, everything checked out fine.

The winters coming so we'll see if I ever get that weird problem with the temperature gauge going sideways again, I'll throw up an update.

[mikeman360]

Ace, I stalled today and when I started the car again I got the same red light indicator for the temperature. I hope after a few days it will correct itself too. How has yours been after your last post?

[dphatch]

Update:

Ever since I had this problem and it went away, its never come back, I suspect the computer just went sideways and fixed itself in the course of a few days later.

Yesterday I went to my mechanic and had a routine oil/oil filter/drain plug change as well as a full scan and checkup for my 997.1. They couldn't find anything error codes out of the ordinary, aside from a couple of engine misfire codes. Aside from that, a near future water pump/rear brake pad replacement, everything checked out fine.

The winters coming so we'll see if I ever get that weird problem with the temperature gauge going sideways again, I'll throw up an update.

Would suggest you include replacing the thermostate when you do the water pump. As the water pumps on these cars are considered wear items by many , I wouldn't wait too long on the water pump replacement. While it may only be showing minor seepage now, a full blown failure should be avoided at all cost and they have been known to fail.

[Mackumz23]

This was available in a different thread so pasting it here… and also the link. Thanks to porschetech3 

One thing that comes to mind after I read this thread, is that the DME has an "expected warm up time map" programmed into it. It monitors the engine temp during warn up and compares it to the "time map" and if the engine warms to fast or too slow it will flag it. Not a lot is known about the map other than it there and compares the "actual" warm up temps , to the "predicted" warm up temps.
 

Temperature guage "failure mode" - Page 3 - Rennlist - Porsche Discussion Forums

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996 Forum - Temperature guage "failure mode" - Having a problem with the temp gauge on my 04. When it is cold out (below 40 F) after driving my 996 for a short while (10-15 minutes) the needle will drop to 0 and the red warning light will start to flash and the dash will display failure...

If you have the tipTronic box definitely worth doing the test of holding up the valve to close it and see if the fault goes away.