On Friday, I had the recalls done. Idle got louder, but mileage has increased too. Anyway, after about 300 miles, the check engine light came on (on a start). Stopped at the dealer this am with the light still on, and they said there was no code stored. Tech said the crimpes at the EBP sensor they replaced were loose, so he tightened them up. How can the light be on, but no code?