etc warning light flashing, vehicle will only go 10 mph

This has happened 3 times since vehicle was purchased with 450 miles. Towed in once, driven the 10 miles to dealer twice. They have reprogrammed main control module & then replaced engine control module but still getting error codes. Tech is communicating with Jeep corp tech but are grabbing at straws. Dealership contends it is my problem. I contend they should purchase it back. Fortunately this happens in my driveway each time lemon law requires 4 instances of similar problem before I can take legal action. Extremely frustrated with Jeep & dealer. Also extremely pissed. Will not purchase another Jeep. My Toyota is 13 yrs. old with 160,000 mi. & has never failed me!