CEL after dealer oil change.

[BIGJake111]

Sent the car to the dealer for an oil change Saturday as well as a slight look over as it had smoked oddly Thursday morning. Got the car back, and drove it this morning, ran great, but I noticed a CEL when parking the car, I do not believe it was on until then, I have checked the gas cap and oil cap, and am unsure as for why the CEL is on.

Idle with the clutch depressed seems high at around 1.1k.

2000 S with 90k miles. Any suggestions before I get the code scanned? Car starts and runs fine, much better actually after the oil change. Yet I have a solid illuminated CEL.