Can anyone explain this?

[hippojam1]

last night i was driving on the 101 freeway in LA which they closed down and made us take a detour through city streets. So it was lots of waiting in stopped traffic and inching up. So obviously I was in going back and forth from first gear to idle, back and forth, clutch going in and out. (I have a manual.)

And the engine temperature started to climb to 190+. (It's almost always at 180.) It wasn't revving above 1500 RPM plus or minus, so I thought that was strange. (And it was 2 am, so it was cool out.)

And then the funniest thing happened. I got back on the freeway from the detour and opened it up, revving up to 5-6000 RPM, to see if there was some sort of problem...and the engine temperature actually declined back to 180!!

Can anyone explain this? Does it have to do with keeping the clutch in for longer periods of time? Seems very odd to me...

[PorscheDoc]

In hot weather at idle, you have no head wind speed to flow through your radiators and cool the car down. Once you start moving faster, you have more air going through the radiator, hence why it cools down. Completely normal.

[RandallNeighbour]

It's completely normal if both your radiator fans are working up front. Check them with the car at idle and the AC blowing and the engine up to temp. Both should be blowing and making a racket.

[hippojam1]

oh, that makes perfect sense. how did i not even think about that? now i feel stupid. i think i'll go return my engineering degree back to my alma mater now...

[RandallNeighbour]

I'm not sure why I second guessed every single thing on this car compared to every other car I've had... must be the fact that I've wanted a Porsche my whole life and I was petrofied that little things were going to be incredibly expensive to repair or I'd mess up the car if I didn't jump on everything I noticed about it after purchase.

I'm sure your engineering degree is handy with lots of work things as well as car issues... keep it!

[hippojam1]

true, i am worried about anything going wrong with my boxster. it's such an amazing work of engineering and design, i love every minute i'm sitting in it. plus, last year before i got the boxster, the engine on my 7 year old audi A4 cracked during an especially hot day and cost $4k to fix. i don't want that happening again.

[RandallNeighbour]

Ah, you're skiddish for a good reason! That would suck and make me freaked out as well.

The longer you own the car, and the more you learn about it will yeild a lot of relief from this feeling. I've owned mine for 2 years and I'm not freaked out about anything that might happen to it now, even the dreaded RMS.

Of course, the long, long list of stuff I've repaired and replaced has given me this sense of security, so it's a combination of things I guess.

Go for a drive with the top down and the tunes up and it should pass!

[986Jim]

Here is the problem. Most cars have a temperature sensor made so that it never moves. It will sit right in the middle of the gauge for every engine temperature from 160 right upto 200. They do this on purpose because if the needle moves around as the engine gets warm and cooler people think there is something wrong with the car and take it to the dealership. Car companies had to literally had to make the gauge read nothing but in the middle unless the car was really overheating.

Porsche puts a real temperature gauge in the car. If you sit in traffic the car DOES get hotter and it shows that on the guage. WHen you drive away and it's getting cool air blowing in a speed it DOES get cooler. The temperature gauge in your car read acctual temperature of the coolant.

Basically (not to be rude) but it's not an idiot gauge like 99% of cars out there, it's a real temperature gauge that displays in real time the real temperature of the car.

[Adam]

Wouldn't it be better to have a gauge that measures oil temp instead of coolant temp? I know some cars have both which would be ideal but us boxster owners don't have that luxary. I would think that knowing the oil temp is more useful...perhaps not?

[986Jim]

Originally Posted by Adam

Wouldn't it be better to have a gauge that measures oil temp instead of coolant temp? I know some cars have both which would be ideal but us boxster owners don't have that luxary. I would think that knowing the oil temp is more useful...perhaps not?

It would but the gauge would move a lot as oil temps can vary across a pretty large range during different styles of driving. Most cars that have oil temp guages also have them dummied down so that people dont think there is something wrong when the needle moves around.

Somehow people have got it in their head that the engine runs at the same temp when floored on the highway as it does when driving around town. As if the engine warms up and stays at this one particular temperature all the time.

[Shrug] I just don't get it.