04 Xuv gas cap loose- effects motor performance?

[Justinm2823]

I recently had the gas cap error code pop up whilst driving. I hopped out and tightened it- I thought. It came on again while I was on the highway, and she seemed to fall on her face st about 70 and limped home when I kept it under 55. After some fanagaling, I got the cap to grab and tighten and everything seems to be slow and good like normal. I can't find anything where the performance should be effected by the gas cap. I'm not terribly car savvy, so I was just wondering if anybody could help

Thanks