after replacing spark plugs still has a little rough idol what could it be?
Plugs gapped correctly? Use a cleaning additive with fuel.
With a coil on each cylinder, one bad coil could cause a rough idle. A good OBDII scanner will pinpiont which one and eliminate a lot of guesswork, especially if that's not even the problem. If you get a readout of "misfire cylinder #X" then you can test that coil and not have to do every one
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