Engine Temp Gauge and Fan

[Bradster]

On my 97 base, and now that it is warming up outside (mid-80's to mid 90's) here in Virginia, I have noticed that the temp gauge after idling awhile at a light will creep by the "0" on the "180" number. It has not gone though the last white hash mark however. The manual just says drive unless the light comes on, but I was wondering what is considered normal. Also, I have never heard the engine cooling fan come on. I assume that is because it is not hot enough.

Thanks.

Bradster

[Lucky]

Bradster,

There are several fans, some of which can run at multiple speeds.

One fan you should hear from time to time is the engine bay cooling fan -- it is behind the right side air "scoop". It isn't very noisy, but it does (and should) start to run on warm days when sitting at a light for more than a few minutes.

The front fans that pull air through the radiators rarely run unless the car is stationary for several minutes. However, when you have AC turned on, one of the front fans will run constantly to keep air moving over the condenser coil -- you'll also notice your temp gauge will move down a bit. Oddly enough, your car will run slightly cooler if you turn the AC on.

As far as is the "0" in 180 too hot? Not really. Most of us see our gauges go that high on warm days. Some believe the Boxster (and most modern Porsche motors) run too warm in their quest to reduce emissions. Some replace the thermostats with lower temp versions (ones that open up at a lower temp). After owning an air-cooled 911 for many years, my opinion is that Boxsters do not run too warm... if they did, they would be spewing coolant in the trunk all the time.

[Bradster]

Lucky,

Thanks for the input. I will listen for the fans and I am glad to know the temp is not out of line.

Bradster

[RandallNeighbour]

Brad, you can check to see if the fans are working properly if you like. Turn the AC down to the coldest setting when the car is fully warmed up and leave it running.

Ahead of the front wheels under the bumper cover you should feel hot air blowing down toward the ground. If both are blowing, you're good.

The temp gauge does move around on our cars... fortunately. It's a real temp gauge.

Believe it or not, the newer 987's do not do this... they put in a stupid one that shoots to the same place X minutes after the motor has been running and never moves unless it overheats, in which case it shoots to the red zone.

[Bradster]

Thanks! I'll do the AC fan test next time I take it our for a spin.

[jmatta]

The temp gauge in the Boxster is terribly inaccurate. What may register 180 at the gauge, is more accurately 205 to 210 actual coolant temp. As mentioned earlier, Porsche runs the temps high due to emissions control at the expense of engine longevity. I run the LN 160 degree stat which keeps coolant temps down, translating to lower oil temp.

If you decide to keep the stock t-stat and run the higher temps, at least do your engine a favor and change the oil every 5 to 6k miles.

[Lil bastard]

If you're not hearing the fans, you probably have a bad ballast resistor in the fan wiring - very common problem.

Porsche sells a replacement resistor which you splice into the fan wiring which lives under the front wheel liners - very easy replacement.

Cheers!