I believe my STS has only shown the message once, and it was down about 2.5 quarts.
Don't panic yet, these cars do use oil, by design. I'd use the dip stick, and keep it at the low end of the fill line. Use Dino oil, and change the oil based on the display. Remember to clear the oil life after changing!
I'd hazard to guess most cars our year burn at least a quart per 1000 miles.
Still amazed how fast these cars are with a lot of miles!
thats in a 95.
98-04 you must check the oil life percentage simply by cycling through the DIC categories.
in english, hit the info ^ and down arrows on the right of the gauges on the dash and go until you find ##% oil life, where ##% is the percentage of oil life left on your car before an oil and oil filter change is needed. when you do change the oil and filter, hold down the info reset button. you will see XXX% and finally 100% will pop up and you will be once again set to measure your oil consumption/expiration.
OH, and to be more on topic, the crankcase for the N* will hold up to 8 quarts
word to the wise about over filling the crank case.. this applies to the transmission as well..
If you over fill the engine.. even by a half quart, you run the risk of areiating the oil.. causing small air bubbles to be dran thru the engine.. This is a VERY bad idea for the bearings.. they will NOT be happy.. It's kind of like if you were in a boat and suddenly, the water was full of bubbles undernieth it.. say bye bye to the boat.. she's going to go under.. this is the same with the crank or connecting rods.. the oil film will have tiny air bubbles in it and this can cause direct metal to metal contact with the bearings and crank journals. I have also seen this on transmissions.. overfilled transmissions will last maybe 1000 miles if that.. due to the same principals.
Also.. I ahve a 94 eldsorado and my oil life reset is the same as described above for the 98-04 cars.. just cycle thru the DIC and just press and hold the "reset" button until it reads 100% again.. usually 5-6 seconds. The only thing I have ever seen the gas pedal used for is to clear an engine flood.. if you depress the throttle before you turn on the key, this effectivly turns off the fuel injectors while you crank the engine.. I can't remember the actual term that was int he service manual, but it is like "clear flood mode" or something to that effect.. this will just pump air intot he engine and hopefully clear out the fuel.. this was on a 1989 olds Trofeo I used to own.. the cam sensor magnet came off which pretty much screwed up the injector firing order. It would run, but you'd have to get it started first..