I have a 2002 Dodge 1500 4 door 4x4 with a 360. The "Check Engine" light came on. The dealer said that I had a fuel pressure leak and that it was the gas cap seal. $145 for the diagnostic, $8 for the seal. a little for the labor, and $185 total with tax.
I said that I'd put it on myself. He said you'll still owe for the diagnostic. I said, "Put it on". That Bites!