I've noticed that upon starting my car I get a smoothe idle. Drive the car for awhile still a smoothe idle,no problems. All of a sudden I notice a slight miss, then the miss gets more pronounced,then even more pronouced over a matter of minutes, even when I start to drive the car it's running very rough,even shaking alittle, all of a sudden the car smoothes out again.
This has happened since just before Christmas.
The items that've been changed since the summer include:
spark plugs, fuel filter and pump,coolant temperature sensor, oxygen sensor, overvoltage protection relay and going to have the catalytic converter changed tomorrow(it's clogged).BTW,200K mis., on the car. Anyone have any ideas? I'm going to set up an appointment for a diagnostic check next week. Thanks