abe

I remember reading that Porsche "fixed" these gauges so that it always reads 175 because people were complaining when there gauge read higher. I noticed that cold or hot, up or down hills...that gauge always reads 175. The oil tempt may go up...but the water is fixed. Am I the only one that finds this a little insulting....shouldn't the gauge read the true tempt?

BTW, I am talking about coolent temperature not oil.
abe

Edgy01

I can't but agree. Apparently, it DOES read a higher temperature but only when it really gets up there. One of the problems with designing these cars more for the masses is that the true enthusiasts wind up with compromises. We can watch the water gauge for any sort of trends or heads-up that something is going on.

As I understand it, Porsche got a significant number of inquiries from a bunch of novice Porsche owners about the coolant temperature and what it "should" be so they decided to "fix" the problem and what we have is the result.

I will contact my Porsche service manager to ask if this filtration can be unfiltered via software. (He's the one who admitted to me that he has seen higher temps from these gauges but only when they are really severe.).

GSIRM3

Yours reads 175 when you first start the car? Most cars I have driven lately seem to have a rather stable water temp, once it reaches its "normal" operating temp. With a thermostat that controls flow through the radiators and aux fans that turn on when the water temp strats to get above "normal" it is not too hard for me to believe that the water temp stays fairly constant, once it reaches normal operating temp.

kauai_diver

You have to drive it consistently hard a while for it to climb over 175. I don't remember mine exactly but close to 190 after a several laps.

The only thing that bugs me is the tire pressure monitor. Before the starting on the track I lower my air pressure and I get the warning. Then when the tires heat up and are back to normal pressure the warning light still stays lit! Ugh ok rant off.

OCBen

+1

Thanks for saving me the trouble of having to type out that response.

The near steady 175 is a testament to the excellent temperature control system of the 997. It just seems absurd for anyone to believe that Porsche would deliberately decalibrate the temp gauge so that it reads a constant value just because there might be some ignorant owners of 997s who are unaware of fluctuations in temperatures of an automobile engine, and that because of this ignorance Porsche would be forced to create an illusion just for them! Wow, that's got to take the cake!

Dr_KarlB

I guess you never had a 996 then ;-)
That gauge was all over the place and it freaked lots of people out.. had fans and a thermostat too.

Most manufacturers dumb down the temp gauge reading for this reason... check out renntech to see the number of questions on this topic for the 996

OCBen

Really? I wasn't aware of that happening on the 996.

My guess is that the guage may have been desensitized by the use of electronic averaging circuitry that filters out temperature spikes and averages water temps over a given period of time. The signal then is sent as a voltage level to the temp gauge, which really isn't reading real time actual temperature fluctuations, but average temperature. It would still be accurate, as far as averaging the temps over a set period of time. And if the average temps start to climb over 175, this would be seen on the gauge, as some here have indicated that it does.

Edgy01

Trust me, Porsche has dumbed it down. Has anyone here ever seen their coolant temp read OVER 175ºF despite driving it hard in hot climates?

1999Porsche911

The 175 on you gauge is wrong. Your actual temperture is substantially higher than that once the car is warmed up and will never back down to 175 when the engine is running. Your car has a 182F thermostat. Your normal actual coolant temperature is probably closer to 190+.

Dr_KarlB

I think they just make the gauge non-linear.

The middle part where the needle usually sits is like 140-220C... if its in the hot region then its REALLY hot and the low end is REALLY cold.

Crazy Canuck

Yes. My fan control thingy failed and in traffic my temp rose and rose and rose. Once underway at speed it was ok.

OCBen

Yeah, that makes better sense.

abe

Also, its pretty ignorant to think that a large variation in out side temp/and driving conditions is a tribute to the germans able to get those controls just right.....sorry that does not fly very well with me. The non linear gauge makes sense....which means Porsche is dicking around with you.
That is not the way is suppose to be....IMHO!
abe

kauai_diver

I don't think the water temperature gauges for the 997 engine are non-linear.

The 3.6 and 3.8 engines were designed to run coolant @175F under normal operating conditions. For most driving and for 95%+ of the time, aside from warming up you will be at 175F. And remember this is the coolant temperature, not metal, oil or air temp.

It's only under consistent hard driving this number creeps up. Wish I could have kept a better eye on it the times I've been at the track, but certainly will do next time. All I remember was seeing it at one hash mark passed 175 which is what, 25 per hash mark?

"175 | | 250" So I was at about 200F probably less... the visual part here is not that accurate I agree, only if they had a digital read out That would drive some nuts though.

**************

Here's a shot from 2006 of my dash after a spirited run up highway 9 in n. California, idling at a rest stop on hwy 35:

1999Porsche911

The engines WERE NOT designed to run at 175F. The thermostat isn't even open at that low of a temperature. Target temperature is 190+.