Did search. What is the deal with the oil measurement in the onboard computer? Mine is all over the map.

Just bought the car. Oil was at the bottom third, ie first tick mark. Added oil (Motion 5w-40), drove, and added a bit more til I got the indicator reading at the third tick mark ie 3/3 full.

Did a short road trip of about 350mi yesterday, and my heart sank when I checked the oil upon return and saw it back at the first tick mark. Had I just bought a car with massive oil consumption?

Without adding oil, I drove it briefly this evening and got readings all over the place: two were back at the third tick mark ie full, and one or two were at the 2/3 mark.

Is the oil measurement function reliable whatsoever? If it’s not, is there any way to verify what’s actually in the sump short of an oil change?

 

Make sure that you measure the oil always on the same spot and a flat surface. I measure mine where it is slightly inclined up or down and it makes a big difference.

Best

 

If this is a 997.1 the only oil measurement that counts is the one you take before starting the car after it has sat overnight.

If this is a 997.2 the motor needs to be fully warmed up.

 

This. Even very slight nose-up or nose-down attitudes make an unfortunately large difference in measurement.

 

Great points. Thanks guys. Think I’ll try to find the flattest spot in my driveway and try again.

 

I am sorry but this may not be correct for 997.1

Engine needs for be fully warmed to measure oil. It's on the manual and also advised by Porsche Tech.

Best,

 

2009 C2S 200K miles

When you ask these questions, you need to denote .1 or .2 cars... or year/model. The engines in each is very different and operate differently in many cases such as oil measurement. The procedure is different as the computer operation including the actual sensor in the oil pan is a completely different part.

I have posted here for years that my 2009, .2 car oil measurement is wonky. Sometimes, it makes no sense at all. In short, choose a place for measurement and don't measure elsewhere or you will either drive yourself nuts or overfill your sump. Of course, your garage is the place. For oil changes, I would not trust anyone but the dealer or myself to do an oil change for fear of overfilling. I have done 99% of my own oil changes every 5K miles. When I do my own oil change, I always measure what comes out and put just that amount in... or maybe 1/2 quart more if I started with the computer noted I was at the bottom of the scale. Then drive up to temp, check the level, and wait until the next day and another measurement before topping off.

I have been threatening to replace the oil sender for ten years now but after reading so many questions from new owners that I came to the realization that .2 cars are wonky. They just are.

BTW, your oil will fill with water from condensation unless you get the car up to full temp for at least 20 minutes or so... this will evaporate off the water... failure to do this can lead to oil level surprises... run a few weeks on short trips then blow it out and you may find a big drop in oil level leading to drawing wrong conclusions.

BTW, we are unfamiliar with Motion lubricants... while very controversial, Porsche recommends only oil with the "A40" specification... it will be denoted on the bottle. "A40" is a special formulation determined by Porsche with cooperation from the oil industry. Many here think it is a scam or a sub-optimal oil. For that, I will leave to you, but I am just making you aware if you are not already, that Porsche does have a specified oil formulation for your car.

Peace
Bruce in Philly (now Atlanta)

 

I measure my garage with a level to make sure is completly flat, which it is, and I always measure there, which I trust.

 

On a 997.1? I've only seen it mentioned that the engine must be cool/cold , unlike the 997.2. I'm a noob so I may be off base..lol

 

my.2 never fluctuates, as constant as the north star. I go one bar below max for the air oil separator and it never moves, not even the day before the next oil change a year later. I do typically check it at a flat gas pump or the garage.

 

What year is your car? I always wondered if this oil wonkyness is the result of an early run of parts. Interesting that even after 15 years, there is no increase in the part's sequence number... it is still 948 606 150 00. Of course it could be a rev in the computer software too.

Peace
Bruce in Philly (now Atlanta)

 

997.2 ... Fully warm and standing at idle for a period of time or the computer will not take a measurement.

997.1 ... Motor off and sitting long enough for all oil to return to the pan, which can take a very long time.

At least that's the way it's been described on this Forum and applies amongst the group of friends whose cars I care for.

 

In the places I have lived, garage floors must slope slightly to allow water to drain. But this slope is usually very small. Consistency in the place you measure the oil is the important take away.

 

The minor (2 degree) slope in my garage floor accounts for 1 to 1.5 bars of difference in measurement (997.2) depending on which direction I park the car. A flattish sump leads to high sensitivity, I suppose.

 

So.... now think about this.... if such an incredibly minor slope results in such a high difference on the scale, why does Porsche think its customers will do the correct thing and not over or under fill this sump? I suspect the engineers designed a lot of slop in fill requirements. In other words, over or underfilling by some margin is irrelevant. If it was critical, these engines would be blowing all over the place... do you think the average owner is anywhere near as neurotic as those on this board?

Besides, the car is a sports car designed for light track use. This means the oil in the sump will be sloshing in all crazy directions and therefore be in a constant flux of over-under-filling. I think it is good to be concerned, but there is a limit to how far we should let our neurosis take us.

Peace
Bruce in Philly (now Atlanta)