Running hotter after 30K service?
 

I have a 2000 Carrera Coupe that just turned 30K miles. I took it to Momentum Porsche in Houston for the 30K service. Since then I have noticed the coolant temperature at times climes higher than before. Could the engine be running hotter with the new plugs? By hotter, I mean the water temp gage climbs close to the post between the 180 and 250 marks. I don't know what is normal for this car as I bought it in April of 2011.

OK, to be more specific: I took the Carrera out for a highway drive at highway speeds. The water temp stayed just above the 180 mark the entire drive.
When city driving and idling more than driving, the temp needle rises close the the mark between the 180 and 250. I did not notice this prior to the 30K service......
Is this much to do about nothing?

I am not a 996 expert by any means but here are my thoughts. First, I can't think of anything in a 30k mile service that would impact the cooling system unless they found you to be low on antifreeze and added a bit.

Second, this time of year I would guess your daily temps are in the mid-60's. So I would seriously doubt the fluctuation is normal, maybe in the heat of the summer, but not now. Perhaps you picked up some trash on one or both radiators? There is a great DIY video on how to clean them.

Otherwise, I would take it back to the shop for further analysis.

A temperature of 250 is too high. If coolant was drained/changed for any reason, there is always the possibility that air can get into the system and not be properly purged. To do this properly requires a vacuum-type tool. Air in the 996 cooling system can definitely cause problems that include hot spots in the engine and resulting damage. Ask the people who did the work if any coolant was drained.

No, you misunderstood me. the temperature needle comes close the the left side of the mark BETWEEN the 180 and the 250 marks, the one without the annotation.

|_______|_______|
180.......................250

__^___^

normal
............My concern

I would be very nervous if my 996 registered temperatures that high on any regular basis. My car does not get much above the "zero" of the 180 marker, even when I am thrashing it on a track at 5,000 ft. or climbing a long run up the mountains in the summer.

If You are getting a "blinking" temp light on the dash that could mean low
coolant in the system..
After a good run with the car, check the coolant level. Burp the coolant system.
Crack open the coolant fill cap slowly and let out the air. Make sure you have
the correct amount of coolant in the system. You might have to do this three or four times to get the air out.
Anything to the left of the middle graduation line between 180 and 250 and you
will not hurt your Porsche.
I don't know if taking it in for service has anything to do with the hight temp.

Check your front radiators and make sure you have no obstructions.
In my opinion if the temp is reading at the line between 180 and 250...
you need to get it diagnosed and fixed.
200 degrees is ok but running your 996 at 210 is a little to high in my opinion.

If the car is getting hot in traffic one of your fans might have a blown ballast resister. Make sure that both run on low and high speed.
Also look in the radiator inlets to make sure that someone didn't leave a shop rag in there.

Thanks for the replies. I am going to take it back to Momentum Porsche.

Post a pic of where the gauge is running.

The dealer told me that during the 30K service, they checked the operation of the radiator fans using the computer to turn them on and off. They checked out OK. BUT they discovered a mechanical reason the fan was not turning on. The part cost $150 and the total price to install would be around $550. This includes removal of the front bumper to access the fans. During the 30K service, they noted that my low tone horn was not working. Replacement requires removal of the front bumper. So I will have the horn replaced when they go in to fix the fans. Part is ordered and replacement will take place this week?

Not hard to pull the bumper cover to clean the radiators.
Porsche 996 986 bumper removal - YouTube

The part was a resistor that had to be soldered in. Had it done yesterday. The resistor controlled the hi-speed fan that comes on at idle. Cost me $515, they installed the low-tone horn I purchased from Pelican Parts for $15 for no extra charge.

Good Dave then Problem solved. I have the 99 996 and it runs when hot at just over 180F maybe a 3rd between the middle line and the 180 mark. It may creep up if I am in traffic but I doubt it as the fans should come on then to cool the rads.