So I changed my plugs today twice (first time the plugs were the wrong ones) and now my car runs like crap. It runs rough, very rough. I've redone it several times and its still running really rough, engine now reaks of oil. I'm freaking out and have no idea what's wrong. Any suggestions?

 

You didn't cross your spark plug wire's did you? What brand spark plugs how was it running before hand?

 

It's a 2000 xj sport so there are no wires and they were champion before and now they're autolite. It ran GREAT before and now it's terrible there's even a knock. I'm completely stumped

 

I just realized that one of the spark plugs was missing a washer when I installed it. Could this be the problem?