2002 Chrysler Concorde 3.5ho

This car has 65000 miles on it, My wife has babied it. It started one night that the dash lights would change for dim to bright Then later the check engine light came on and the gas pedal has to floored before it will go, and it has plenty of power. The mechanic we took it too changed the 02 sensor and the tbp sensor and nothing changed. He recommended that we buy a another car. I noticed the cruise control doesnt work, so I am asking if there may be a fuse or some simple problem, may a bad ground or if you have had anything similar. We bought this car new and its paid for, we would love to figure it out without spending too much at a dealership. I would love to hear if you have any solutions. Thank you