I had my first oil change on my 04 996 today. The dipstick shows full level where the OBC shows 2 bars below level. It held 9 quarts. I'm afraid to put anymore in. Will it over flow if I do or can I damage the engine? The engine was hot at the OBC reading and cold on the dipstick reading. Thank you for your time......Dennis

 

The electronic guage is a helpful tool to have every time you start the car but the dipstick is the most accurate.

 

Just 2 bars below the max line with the oil hot is ok. You can add some oil, say 1/3rd a quart, and this should have the oil level at nearly the max line but there's no reason unless you want the reading right at the max line.

If the oil change was done by a knowledgeable shop it would have checked the correctness of the oil e-level system.

This requires the engine be "hot" (70C?), and the oil drained 20 minutes. There is a specific amount of oil to be added to the engine after a 20 minute drain (and filter replacement).

BTW, there is an overnight drain period too, after which a bit more oil is required.

(The new DFI engines have a one hour drain interval.)

Anyhow after the drain interval a specific amount of oil is then added to the engine and the e-level checked and the reading confirmed correct given that a *known* amount of oil was added to the engine and the e-level reading is right where it should be.

At oil change time with my 02 Boxster I use the dipstick just because I'm too lazy to count the empties. I verify there is oil showing. (With the Turbo it has no dipstick, so I count the empties, twice.)

After that whenever I check the oil level in my 02 Boxster (and Turbo) I use the e-level system. I keep in mind several things. The levelness of the car or lack of levelness affects the reading. (It affects the level displayed on the dipstick too.) (The Turbo oil e-level system does not "take" a reading if the car is not level enough.) So I'm careful to check the oil on level ground. If the ground is not level I know this can affect the reading. In severe cases -- parked against the curb on a heavily crowned road -- the level can be very low, low enough the e-level display flashes. However, because I know my car I know the level is ok.

Another thing I keep in mind is the oil level varies by temperature. Cold oil can have the level 1 maybe 2 bars lower than it would be otherwise.

So cold I like to see the oil level 2 bars below the max line. Then when hot and I check the oil the level will be at the max line and I'm good and so's the engine.

I keep pointing out that oil changes with these cars is more than just a time to refresh a vital fluid. It is the right time, the only time, the correctness of the oil e-level system can be verified, provided the shop knows what it is doing and does what it is supposed to do.