2004 Crossfire Coupe. Road for 80 miles in 99 degree weather and last 15 miles 104 degree weather. Sat parked for 2 days and when I started it the check engine light appeared. Dealer says diagnostic test revealed there is a gas leak, however, no leak has been discovered. Any other recommendations?

 

I'd recommend that you read the code(s) that set off the light. We can guess all day but that won't help you.

It sounds to me that, very likely, what the dealer was saying is that the system failed the pressurization test that it does periodically. if that is the case, it may never come back. My Graphite would throw that code maybe once a YEAR. I never figured out what it was seeing.

So, what code(s) were stored that caused the Check Engine light to come on?

Did you know that you can buy very cheap OBDII readers that you can read your own codes with? Also, most any auto parts store will read codes for you.

The purpose of the Check Engine light is to tell you that the system has stored a code or codes. By reading the codes(s) you will know what the ECM is seeing and you can act accordingly.