Plugs or Coils?

[Tweedle335]

Last couple of times I've done hard pulls I've thrown the same codes. They are always misfire codes and I always get the rough idle with the SES light right when the codes are thrown. The only performance mod on my car is a jb4 on map 1. Is there any way to tell if this is my spark plugs or my could? I've read about problems with both, but is there a way to tell if it's one or the other?

 

[R.G.]

Real easy. Swap the coil from misfire cylinder to another cylinder. See if misfire follows coil.

Welcome to the forum.

 

[ATL-IS-N54]

Yes do this... Swap the misfiring cylinder coils to a proper firing cylinder and see if the problem follows, if it follows its 100% coil, if it doesn't it's 90% plug

Real easy. Swap the coil from misfire cylinder to another cylinder. See if misfire follows coil.

Welcome to the forum.

 

[ATL-IS-N54]

I just did new plugs and a coil on cylinder 5, and a set of 6 coils just to have on deck for this motor...