My question involves a consumer law issue in the State of: Illinois
I recently purchased an used 2006 Chrysler 300 (close to 90k miles) from an used car dealership in Bridgeview on June 7, 2013. When I purchased the car and drove it off the lot, it was fine. During the ride, the service engine light came on. I took it to auto-zone on June 8, 2013, they diagnosed the problem as catalytic converter defective low bank 1 and low bank 2, along with sensor failures. I took it back to the dealer, they said they fixed the problem: the service engine light goes off. The next couple days passes, the service light comes back on. I took it back to auto-zone, they diagnosed the problem as catalytic converter defective low bank 1 and low bank 2. I took it back to the dealer, they claim they fixed it again. June 17th comes, the service light comes back on. I take it back to the dealership, they keep the car for 4 days, state they fixed it. June 21st comes, the service light comes back on. I took it back to the dealership, they keep the car for 8 more days. They state they fixed it. July 10th comes around, the service light comes back on. I call the dealership, they inform me to pay for a Chrysler dealership inspection and bring the car back and they will fix all of the problems that's listed. I take the car to a Chrysler dealership, they perform the inspection. A ton of things return from the inspection that deemed the car "unsafe to drive." I take it back to the dealership, they state that Chrysler is "over-exaggerating" the damages to the car. They refused to service the car. On July 13th, they state that they will perform the services but I will have to cover 40% of the charges. Paid 40%. They perform the services. July 31st comes around, the service engine light comes back on! Each time the service light came on was for the defective catalytic converters. They never replaced the catalytic converters, and I have documentation stating that I paid for services to replace the catalytic converters. What are my options legally?
(I know it's a bit much but I have receipts for all auto-zone diagnostics, and mostly all receipts for work done on the car, I have all diagnostic reports from the Chrysler dealership, I have written/signed statement from used car dealership stating repairs are paid for that included the catalytic converters)