Recently my 05 impala has been acting up. The check engine light sometimes comes on, but it's always acting weird. The code is multiple/random cylinder misfire. My car shakes when idling or when I'm coming to a stop. It has shut off 3 times, once while exiting off the interstate and twice while turning. The blinkers sometimes stop working, the green arrow comes on and stays constant, doesn't blink. I fix that by turning hazards on and off multiple times quickly. I have replaced plug wires and used a fuel injection cleaner. The car has about 220,000 miles on it but I keep it maintained.