on these kind of things.

I've hated every last one I can remember. I will do my absolute best to not use them. Warranty service is terrible ("it'll take us 2 days to diagnose it, and then if it falls under warranty, we'll give you a loaner vehicle...if we have one, then it'll take us 2 weeks to fix, cuz...you know&quot general service is even worse. I've heard two service managers bragging/comparing how much money their area has brought in that day. Like, I'm sitting right here while you write my estimate.

I must say, my brother loved his dealership experience at Lexus. Not gonna buy a Lexus for a dealership experience.

Warning messages or lights show up if a control module(computer) in your car senses a problem when it performs a diagnostic test and sets a trouble code. The loose fuel cap message means that the engine computer detected a leak in the gas vapor containment (EVAP) system. Some tests are performed very frequently, others are not. EVAP system leak tests are not. The test might run once per drive cycle, IF multiple conditions are met. So if you are driving once a week, this test is running infrequently. The most common reason for a leak is a loose gas cap, but there can be many other reasons. If the cap was not loose, there could still be a leak, and the code may reset...eventually. If he didn't charge you, I doubt the Midas guy actually tested for leaks, which is the proper way to diagnose this concern.
If a problem such as a loose cap is fixed but no one erases the trouble code, the warning light will not disappear immediately. It should eventually go away if the computer runs several tests that pass. How quicky that happens depends on how frequently you drive. Auto parts stores can usually scan and erase trouble codes for no charge, though some state laws may prohibit them.

Well, we can look it for $100 then tell you what it will cost to repair, then charge you for the repair.

Used to be, take a look for free, tell you it’ll be $100 to fix it, then fix it and charge you for it.

But that leaves an income opportunity out so we can’t have that.

You also may just not elect to fix it in which case they are out the diagnostic time, so I do understand that at some level.

on our Tundra. It turned out that the hose from the fill spout to the gas tank was degrading around a junction of some kind. It was older than that. Your problem could return and it might not be the gas cap.

Best of luck.