jlkline

I've read the threads here, on other 997 forums, and contacted several dealership service departments and can't get a consistent answer!

My car is a 2005 997 (997.1) C2 coupe.

Last night, after driving home from the office, I checked the oil level. I shut off the motor and waited for the timer to count down (about 5 minutes) and give me the reading. It was right on the "min" line. OK. I said, I'll go buy a quart of 0w-40 and add some. But then in my infinite wisdom, I decided to wait until morning and check it again dead cold (as cold as it can be living in Austin TX and after 6 seconds it read 1 full mark above the "min" line! (each mark being about about 1/3 of a quart I think). BTW, my garage is dead level.

The manual is a bit nebulous about engine temp for checking oil level too, so I want to put it out here again and see if I can get some help!

I've been a 911 owner and wrench turner for 25 years, but this is my 1st venture into the liquid cooled...I damn sure know how to check the oil in the air cooled cars!

Thanks, and apologies if this topic has been beat to death.

Bijan

Oil level is normally measured at around operating temperature, not cold. With the 997.2 we have no choice it only measures warmed up oil and with engine running.
You would have had some more oil settle during the night slightly increasing level. At this point I would only add half a quart and monitor the level, it need not be at the top end.

PhilD

997.1 will measure it cold and it does appear to take into account the volume difference between hot and cold as I always get the exact same reading whether hot or cold. It could be that it's just real close to the point between the two with yours, and as Bijan mentions, it could just be that overnight all the oil drained to the pan, which made it jump up one.

I would tend to rely on the hot measurement more than the cold though if they were different.

Personally I would not run it at the min level and always keep mine at the max level.

Petza914

I'm with PhilD about keeping it at the max correct level (top line on the gauge). I have 2 997.1 C2S cars and see too many differences in readings when checking the oil level when warm, even after the timer has counted down. I check mine first thing in the morning before I drive the car. If I get a reading that shows 1 line down, I check it for a couple more days due to the inconsistency of the automatic gauge. If I get a reading 1 line down for 2 or 3 consecutive times, I'll add 0.4 quart, which is what someone on this forum meticulously calculated was the difference between lines on the gauge. Adding 0.4 brings it up to the top mark every time, but not beyond.

JW911

Yes 997.1 should be checked cold. Easiest to just do it before you start the car for the first time of the day. Takes 10 seconds instead of 5 minutes.

RollingArt

The computer adjusts the level display for drain time and oil temp.

First start of the day should be the most accurate reading. Computer doesn't do any adjusting to the level for any of the warm temp conditions.

From the workshop manual:




.

kcheves

For future reference, the 997.2 oil level measurement is different. Per the manual, the measurement must be taken with:

- Vehicle stationary
- Car parked on a level surface
- Engine at operating temperature (140F/60C)
- Engine must be idling

Minok

The manual for the 997.1 should tell you what the procedure is, follow that. It is different than the 997.2 procedure. Follow the process for the car - the car should just do that via the OBC system.

If you check in the morning, there is more oil in the pan than if you check just after the engine was shut off, as oil continues to slowly drain as the car sits with the engine off. So over time, the oil level may increase slightly.

The segments, as others have said, are triggered at certain levels - if the oil is near such a transition point, a small increase can show as an additional segment being illuminated, or not. Don't sweat it.

And in the end (my strategy) is to stop obsessing about the top line on the display levels, that should NOT be your target level of oil. Any amount of oil above the minimum is enough oil for the system to work. Target the oil level near the middle and you are good. If you try to hit the top line, it just increases the odds of an overfill, which actually IS bad (not all the warnings in the manual about that top mark). Being in the middle or bottom 1/3rd of the range, no the other hand, has no adverse affect.

Bijan

Minok agree with you. We have more than 7 quarts of oil in our cars, aiming for the top segment could easily result in over filling. Better to be between min and max.

Rotmilky

I keep a log of driving conditions for my car each time I drive it. That log includes oil temp, oil pressure and oil level over an approximately 20K mile period. Looking at my log, I find that my oil level measurements vary by about 2 ticks.....or maybe I should state +/- 1 tick. I shoot to keep it at the 3/4 mark. Then it varies from full to 1/2. Maybe the computer attempts to correct between cold and hot, but at least in my car it's pretty crappy at doing that.