Bruce In Philly

191K miles C2S

Ok, I am really getting annoyed. I have posted before that my car oil level readings can be wonky... and consistently wonky for 10 years. But now I am getting more annoyed. Opinions? Anyone have the same symptoms?

I just changed the oil a few weeks ago... I filled until the dash meter was full to the top line. Drove, drove, and drove. It dropped one click... OK, so far so good. I then go on a 5 hour highway drive, come back and I am at the bottom line. I think it is wonky... drove the next day running errands, come back and now the below-line marker is flashing. I parked and ran the car to hot the next day and checked again, yes flashing. oh oh..... so I am burning oil (exactly 2000 miles since oil change) ? So... I add exactly one litre. My manual notes min to max is 1.25 liter. What did it read from flashing low with 1 liter added? Solid full... at the top line. WTF?

I have noticed for 10 years, that it drops slowly when full and faster as it is used... but this is very accelerated behaviour.

I think I will finally change that sender at my next oil change.

Anyone do this for a .2? Does the unit need some sort of calibration by the dealer?

Peace
Bruce in Philly (now Atlanta)

voiceprint1

I would say this can occur with drastic weather changes, or driving then sitting for a while. I have had this exact low light warning only to top off to top mark with 1qt added?, no reason other than temp change/infrequent driving I think. I think when the oil is changed quite a bit of oil is stored in the new oil filter, giving false readings. Just my 2 cents.

GKGEIGER

Isn’t there a printed quantity for oil change with filter replacement. If there is, that’s what I would install.

Optionman1

Owner's manual has fluid capacities listed. For my 09 4s it says "Oil change quantity with oil filter approx. 7.9 quarts/7.5 liters". Not sure for C2S.

BucketList

My car uses oil very slow or not at all for about 2000 miles, then burns down to the bottom over the next 1000. 1/2 Qt gets it back to halfway. I attribute this to the oil losing its shearing film strength. Now I have noticed that when I drive a lot of short trips the oil level doesn't change that much until I drive a long highway trip when it drops 2 bars. I attribute this to water vapor adding volume to the oil which doesn't evaporate in short trips but does on long highway trips. Thoughts?

Hella-Buggin'

The short trips might be replacing burnt oil with condensation. A long trip will get the oil hot enough for a long enough duration to evaporate the condensation from the oil.

bheit1

I can only speak from my own experience. I have 23k mi on my 997.2. It's used a few times during the summer when I
can get it thoroughly warmed up and drive a hundred miles or more. I find that following the owners manual of not filling the
top section of the gauge is too full. A few years ago I replaced the A/O separator because it was contaminated from over filling.
It would let out a cloud of blue smoke at startup. I always leave the top two oil gauge sections empty now and that seems to have
taken care of the problem. Since I don't put on many miles I have not noticed any oil usage between changes.
Oil is changed every fall before storage.

plpete84

Sorry I don't have the source but a while ago I read an interesting technical article about the coefficient of thermal expansion on oils used in cars. The article concluded that cold vs hot oil can have a change in volume which is as great as 5%. Oil does expand with temperature so it made sense to me. If your car holds 8 - 10 quarts of oil that can translate to a noticeable difference. This is why it's recommended not fill the oil to the full mark.