Re: Pesky Temperature Indicator Failure?

Lately I'm getting an intermittent “Temperature indicator failure”. This occurs on a couple of times a month and lasts only a few minutes and then it goes back to normal. (See pic).
I checked for OBD codes, but all was clear. I’m guessing Coolant Temperature Sensor is going.

Any recommendations on what to do or not to do when doing DIY replacement


Thanks

First you should consult the owners manual to see what the warning actually means. Yes, I know "Failure Indicator" is pretty clear but....

If you have the ability to monitor engine telemetry via the OBD2 port you can view coolant temperature in real time and see if the reading falls to -40C or climbs to some ungodly high temperature level. Occasionally my Boxster's coolant temperature climbs to the max reading possible. This is due to an intermittent bad connection at the sensor/wiring harness connector.

If you see a bad reading I'd check the connection first.

I've never replaced a sensor on any of my Porsche engines but on other engines it wsn't a big job. I can't recall now if I drained the coolant or not. Probably I did as it made changing the sensor a less messy job and one more likely to be successful as one doesn't want to fight the outflow of coolant in trying to get the new sensor in and tight and leak free.

I have precisely the same issue with my 2008 997 Turbo - the failure is intermittent. The dealer said that he couldn't reproduce it, but it happens very frequently.

I suspect something strange like a bulb is playing up or there's a faulty connection somewhere, rather than the temperature sensor is failing. I have had strange error messages on my console in the past when a rear brake bulb is about to blow, and then, after the bulb has failed and I have replaced it, there are no more strange messages. Gone are the days of simple wiring in cars. We now have optical fibre and data busses!

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Howard in London
I have precisely the same issue with my 2008 997 Turbo - the failure is intermittent. The dealer said that he couldn't reproduce it, but it happens very frequently.

I suspect something strange like a bulb is playing up or there's a faulty connection somewhere, rather than the temperature sensor is failing. I have had strange error messages on my console in the past when a rear brake bulb is about to blow, and then, after the bulb has failed and I have replaced it, there are no more strange messages. Gone are the days of simple wiring in cars. We now have optical fibre and data busses!

Could still be a marginal/intermittent connection. My 996 Turbo's oil pressure gage needle bounces about some at various random times. It is a loose connector probably at the oil pressure sensor/sender but I'm too lazy to try to get to it and mess with it and whenever I take the car in I always forget to ask a tech to do this.