Cayman 987.1 2008 3.4L “S” Temp Gauge reading ?

A quick question, I have recently bought a 3.4L Cayman S 2008 According to the receipts I got with the car previous owner got a low temperature thermostat fitted several years ago. I do not know here the thermostat came from, but the service invoice states: “Thermostat 71C/160F “ My water temp gauge on the dash sits at “180” once warmed up, & has never deviated from that even when stuck in traffic on a 30 deg.C summers day. I have read that the Porsche temp gauge readout is not accurate, in fact HARTECH (UK) believe that it under-reads by about 6-8 deg.C , presumably to avoid owners worrying about seeing temps close to boiling point if it was truly accurate. I would be interested to hear what temp owners who have fitted a low temp thermostat to Cayman “S” see on their dash? Thanks in advance Alan

From what I've seen and read over the years the temp gauge doesn't read low but is rather an idiot gauge. IE the display is very nonlinear compared to the actual input. I've seen info that says it sort of reads true up to around 160F where it reads constant at 175F up to around 190F where it starts rising again. This hides the driver from scary fluctuations from driving to stopped, fans on and off etc. Unfortunately like an idiot light it hides that things are going south until they are. No idea on the low temp thermostat but it would appear that the 160F setpoint would put the operating temp in the constant 175F display range.

Forgot to mention. Actual water temp is on the CANBUS. If you want to know what your car is really doing get a code reader that will display real time readings. Durametric will. I expect there are others.

Thanks Greywolf, I take on board your comments about being an idiot gauge, part of the reason I wanted to find out what other people's gauges read. Hartech say that they found the gauge reads closer to the temp of the cooled water leaving the radiator, rather than the actual temp in the head or near like most cars do. The whole issue is also complicated by the unusual placement of the thermostat where the cooled water enters the motor, rather than the hot water exiting the head, delaying response to rapid temp fluctuations ... go figure

It actually reads middle of the gauge from like 160F up to 220F. It's pretty much useless.

My temperature gauge rises to 175 degrees and stays there, no matter the ambient temperature or driving style.

Thanks

Thanks Chuck, Is your car a 987.1 , and do you have a 'low temp thermostat 'fitted? Cheers

If you want an easy way to get the temperature you can try something like this OBD gauge: Amazon.com I got that one to use on my wife's car. I tested it on the 987. and I'm pretty sure it worked, but I didn't use it very long and I haven't tried on a 987.1 so probably best if you do your own research.

Thanks, good suggestion, I will investigate this, Cheers

Before buying the Chinese gauge from Amazon , I'd suggest reading the 1 and 2-star reviews. I always do that before purchasing something unfamiliar to me from Amazon . Apparently, support for these is actually non-existent. You might consider what I feel is a much better option from Standalone Water/Oil temp and oil pressure gauge for 997 and 987 — 997research

I mean, it's working well for me on the Mini, it's not like it requires any support, and it was $40. The 997research one is very nice and does more but it's $245. You usually get what you pay for but sometimes cheap is good enough.

986 /996 had true water temp gauges. People kept questioning if 170 vs 180 vs 190 is okay, not okay. Starting with 987/997, water temp gauge is idiot, will never move above that unless the car technically starts seeing 235+ A Scan Gauge II (or whatever is newer) plugs into OBD and rest in the lower cubby hole of front console. It shows true water temp. Especially if u have the 3rd center radiator. Spirted drive with AC on (90 outside) and water temp ranges 188-200.