I just replaced my spark plugs, being the first time on any car that I have done this. I have read the other threads to make sure I did it properly. All seems well with the car and it runs, but I didnt notice a difference. It actually takes a little longer to start and I am not sure if it is running off of all four cylinders. I have checked to make sure that the boots are seated well, the plugs are at 18lbs/ft, and everything like that. I dont know how a engine acts when it is not firing in one cylinder. Is it noticable or is it really hard to tell or what? I am just trying to make sure that my engine is running properly. Thanks for any info guys and gals.