I have a 2003 pt cruiser that has been idling rough. I went thru some water and the next day when the problem occur. Took it Autozone and it came back with plugs, wires or coil problem along with either high/low fuel pressure. Changed out plugs wires and coil. Still the same problem, will run fine for about 15 minutes and then it will bog down. I had the car rechecked and it said it had a misfire. Replaced the plugs again along with the coil, the problem remains. What esle can I do? The only thing that comes up is the coil when the car is tested.
Free code pulls rarely identify bad parts, just a failed system.
You need to check compression, fuel pressure, and look for vacuum leaks. Injectors may be an issue as well. My suggestion is to stop throwing parts at it and go to a real shop for a real diag and a bid for repair.