rnl

My 991 base was delivered in June 2012 and I have enjoyed driving it over 93000 miles. The summer delivery provided ample time for the temperature gauge to register high coolant temps. I would often get readings of 225 F and above. Because the system is under pressure it wouldn't boil and it was clearly not overheating.

Early in my ownership some time in the summer of 2012 I received a call from the Porsche store; there was a required reprogramming. From that day forward coolant temp reported temps no greater than 194F...clearly, bogus. probably intended to stop calls to the service department reporting readings above 212F.

Anyone know of a way to de-lobodomize the temp reading to restore accuracy to the gauge?

desmotesta

Very interesting post and i would be interested in what others have to say.

My 991.1S coolant temp always stays at 194 while the oil temp can go as high at 205-210..

My car has 25K miles but I was thinking about adding the OEM 3rd radiator as a precaution and/or long term reliability item. Keeping 10-15 deg down for say 90,000 miles has got to be better for the engine, seals, gaskets, wear etc

Bob Z.

If you drive in Sport or Sport+ the oil will run cooler by about 20 F. You do not want your oil to run too cool either to ensure water gets burned off but 215 F or so is fine.

Carlo_Carrera

Bob is 100% correct. Running at 215 F using quality oil and regular changes will have no ill effects.

LexVan

I only ever look at the water temp to know when it's time to go over 4,000 rpm (+180F). Then all that matters is oil temp anyways.

CSK 911 C4S

Wonder if any one with the iCarsoft computer can read the actual water temp when in Sport/Sport+.

Catharpin

My oil temps lag way behind my water temps. I can be up to temps on H2O and under 100 on oil temp.

LexVan

Do doubt. My water is at 100 backing down my driveway in the early AM. The thermal management of these cars is amazing. Water temps rise very fast. Oil, is very-very slow.

desmotesta

Same here, oil temp was at 64 deg this morning, took 4-5 minutes of driving for it to start moving.

i wait for water temp to pass 110 and I start gingerly driving. Dont like to idle it after cold start, no more than a minute or two tops

DBH

Water temp on modern Porsches are buffered and max out at +/-194F. Actual engine water temp will increase above that but will not register on the gauge. If temp on the gauge starts rising above 194, there is an overheating problem and the idiot light will go on. As a result, the oil temp gauge is the one really worth monitoring.

The next step for car manufacturers is to go exclusively to idiot lights only. After all, the vast majority of drivers view their vehicle as an appliance and aren't interested in anything more than tech features and getting from A to B.

sr5959

I have to drive mine about 12 miles before the oil temp moves out of the Blue zone. Is that about normal?

ClassJ

Those gages are nothing more than idiot lights.

this might be another action for APR to tune out.

LexVan

Yes.

sr5959

Thanks Lex!

arter

Water temp has a deadband ( roughly 194 to 221F) to prevent customer worry when it is in the normal operating range.
If you track your car, you may see it pop out and start reporting temperatures above the normal range ( I have).

The oil sensor ( for the dashboard) is in the pan and lags the oil temp passing through the oil/water heat exchanger ( which is coming from the engine).
The oil heats the water up so it has to be hotter than the water temp ( at least at the heat exchanger)/.