For a few weeks now my 1.8 has had the CEL on with an o2 sensor issue. I've been driving it anyway. This morning about 2 miles from home the CEL starts flashing and the car is running horrible. I turned around and got it home. Pulled the codes and they were random misfire and both o2 sensors. Total of 4 codes. I cleared the codes and swapped a few ignition coils around and changed the plugs out. All the codes went away except one o2 sensor but the car still runs very bad. It almost feels like the catalytic converter is plugged or all ignition coils are bad. What do you guys think could be the problem?

 

did u replace the ignition coils or just swap them around?> The cats clogged will cause the car to bog down but i dont think it will cause it to run rough. Sounds like u still have bad coil/coils???

 

You were correct. I replaced the coils and it runs great. Just threw me off having the random misfire code. Thanks.