[langridge]

Is it possible that the engine runs smoother and is quieter with the change of the spark plugs? I went from stock NGK's to NGK Iridium. My car has about 38,000 miles on it.

 

[InfernoAWD]

i just did that change, went from stock to the iridiums and it does feel a bit smoother, but you can't hardly notice whether or not it sounds quieter and smoother, i did the change because a friend recommended it. it feels nice and i feel a lot better knowing that i did a tune up:wiggles:

 

[jeffmm06]

Yes, they say they will make it run smoother, better mpg. etc. I changed to the same plugs, it seemed to run better, or maybe it was just my mind playing with me. But i think they do!