tamouq

I have a 2004 Civic LX coupe, D17A1. A few months ago I was driving on the highway and the emissions light started to blink. The engine lost a lot of power and I couldn't get it over around 2300rpms. The code was a cylinder misfire on only the 3rd cylinder. Since then it has ran fine but occasionally the light will blink and then stay on but the motor runs fine. Like it would just misfire once and trip the light then be fine. Since then it has slowly gotten worse. It idles very tough and shakes the whole car. The misfires happen every 30 seconds or so while driving. I can hear them and feel them while driving. Sometimes if I keep the pedal pushed in at the same position for awhile the engine will make a rattling sound like it is shaking loose and it only stops when I let off the gas then back on. So far I've ran injector cleaner through 3 tanks and replaced the plugs even though they looked fine. Also replaced the coils and I'm still having issues. Air filter is clear as is the throttle body. My guess is a cam sensor or crankshaft sensor but I'm not sure what to look at next but I really don't want to drive it like this anymore.

80%downtime

find a replacement set of injectors and test with them, or just shuffle your injectors around and see if the misfire pops up on a different cylinder.