Rep Power: 0

Hey everyone,

A few days ago the check engine light came on in my 2003 Civic DX and the car was misfiring horribly (prior to this day the car drove perfectly, no problems whatsoever). Pulled the codes and it was cylinders 1, 2, 4, and random.

So I went and bought those overpriced E3 Diamond plugs because it was all O'Reilly's had. Cleared the codes and the car ran fine. But now the past couple days have been a little bumpy. I can feel the car misfiring (usually late in third gear, especially if I'm merging onto the highway and pushing 3k/rpm) but the CEL has not come on again, and the misfires are "better" than before, but there's definitely jerking.

Has anyone used these E3 plugs before? I've heard this generation is sensitive to plugs.

What should my next step be? Swap around the coils? Toss the E3s and get Denso plugs?

I'm also having heater issues (air blows hot only when moving, cold when stopped) and I think my serp belt is on it's way out, but I doubt either of those would be related to misfires.

 
Rep Power: 210

start by replacing the plugs AGAIN with stock recommended plugs, that will take the plugs out of the equation here, and if you are not very experienced use a torque wrench when installing them

there is no better plug than the stock plugs

 
Rep Power: 518

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No matter what the parts store pushers try to sell you,