Hi all, I have a 2002 Civic DX with the 1.7L. It has 200k km on it so it should have life left in it.

Cylinder 1 is misfiring and I cannot figure it out. I’ve gotten new plugs, swapped coils, swapped fuel injectors. I even did a head gasket and got a valve job done.

After all of that, cylinder 1 is still misfiring. You can really only feel it at idle, but the CEL will blink. I’ve tested compression before and after the valve job, all my cylinders were sitting at 125 except cylinder 1, which had 60. After the valve job, cylinder 1 is now at 110.

What the hell else could I attempt on this?? I’m out of ideas at this point and getting frustrated.

I just bought a leak down tester and will report back when it arrives. But I feel like 110 is barely that different from 125, yet it feels like cylinder 1 contributes barely any power

 

Ok, when you did the head gasket replacement did you take the EGR plate out and clean out all the carbon buildup. Many years ago I bought an Accord with the same problem as yours and the owner had replaced EVERYTHING possible he could think of. That's how I got it cheap. I pulled off the plate, cleaned out all the ports, used a small drill bit twisting by hand to ensure all four passage holes are cleaned. NO more cylinder misfire codes. I just replace the head gasket on my 04 civic and the egr plate on it was nearly stopped up with only 182k miles.