The oil warning light is governed (mostly, at least) by the oil level sensor, which lives in the oil pan.

If yours is on when your oil levels check out well, there's a very, very high chance that the sensor is bad (it seems to be a relatively common failure).

Mine went bad and I had a similar experience: the light would come on intermittently and then came on all the time after the ECU starts checking it (~10s after start-up). Another way to tell it's the oil level sensor is that the electronic oil level read-out won't work right (it'll either tell you there's an error, or just display the stop-watch icon in the display forever). My FSS still seemed to work, but just seemed to reset to 7,000 and count down miles (rather than whatever self-adjusting German algorithm is supposed to be in play).

The part is about $100 and another user did a write-up about fixing it - not the easiest job as you remove the oil pan, but also not very hard as it's the ONLY thing you have to remove (besides the splash pan to get to it)!

https://www.crossfireforum.org/forum...el-sensor.html

Hope this helps!

p.s. when I saw this light on my car, I was really worried too - some places in the service manual claim oil pressure plays a role, but I've never heard of one of these cars ever having a sludge or pressure issue, so I'd say with a pretty high degree of confidence that it's just the level sensor going bad.