"OilOverfill" warning on 991S

[Barnet]

I purchased a used 2012 991S cab two weeks ago with 2,020 miles. A "oil Overfill" warning message appeared after about 200 miles. Porsche dealer said no problem the selling retailer probably added some oil. It will go away after some miles. Message did go away few days later. Now after 10 days the message "oil Overfill" has returned!!! Anybody know what's up?

[JFP in PA]

I purchased a used 2012 991S cab two weeks ago with 2,020 miles. A "oil Overfill" warning message appeared after about 200 miles. Porsche dealer said no problem the selling retailer probably added some oil. It will go away after some miles. Message did go away few days later. Now after 10 days the message "oil Overfill" has returned!!! Anybody know what's up?

Yes, not to sound pedantic, but the car most probably has too much oil in it, which is not a good thing. Check the oil level, if it is over filled, try changing the oil filter which will drain about 1/2 quart out. If that is not enough to get it to the correct level, dump the oil and start over.

[Mijostyn]

Hi Barnet,

JFP is right. Changing the oil filter is the only easy way to get oil out in a controlled fashion. However, these oil level sensors will do funny things under the right circumstances. They read the oil level by bouncing sound waves off the air/oil interface in the crankcase like the wand of a medical ultrasound machine. Stupid things like condensation on the surface of cold oil can mess them up. Condensate can also increase the volume of the oil. if you are full up this can push it over the top. I had an Audi which gave me the overfill warning on several occasions in error. Since I changed the oil and as far as I know there are no oil adding gremlins in my garage I ignored it. You really are only interested on low oil levels. The car did not do this for the last 6 months I owned it. Now I have a pretty yellow 911 that blows mildew in my face every warm morning when I start it up. Ferdinand would be proud.