If the check engine oil light you refer to is the check engine oil level light (looks like a pump oil can), then there are two possibilities for the discrepancy:

1) The oil level sensor could be bad. If it isn't #2, below, then it is this by default. See your dealer.

2) The reading you are getting on the dipstick may not be accurate. Ensure that the engine is warm, and shut off, and that the vehicle has sat for a few minutes not running. The vehicle must be level. Take a few readings, wiping the dipstick clean each time. If you continue to get readings between add and full, then see your dealer, as above. I suspect that the oil will drain down and that you will need to add a quart, but that is just a hunch.

Good luck.

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2007 X3 3.0si, 6 MT, Premium, White

Retired:
2008 535i, 6 MT, M Sport, Premium, Space Grey
2003 X5 3.0 Steptronic, Premium, Titanium Silver
2002 325xi 5 MT, Steel Grey
2004 Z4 3.0 Premium, Sport, SMG, Maldives Blue