Hey guys. So a couple of days ago I was dropping a friend off on a very bumpy street (this could be irrelevant). I was driving away back down this street and the CEL came on. I immediately went to Advance Auto to have the code checked. The only times I have thrown codes in this car previously were from failing to tighten the gas cap enough and when I broke my knock sensor replacing the starter (knock sensor was replaced with new OEM Honda sensor ~15k mi ago at this point). Well, the codes came back as being a misfire on all 4 cylinders. I must mention that the car has been running and idling 100% fine lately. A friend and AP2 owner took a ride with me lately and noted that the car was pulling hard. At any rate, this news worried me quite a bit. Later that day I reset the code myself to see if it would return quickly. At this point I have probably driven 50 miles since resetting the ECU and the code has not returned.

My car is 100% stock other than a quick-swap stock exhaust or downturn after the stock resonator. Stock cat. Spark plugs were replaced with NGK Laser Iridium around 1,500 miles ago - by me, very meticulously. I have never overrevved it myself, though I can never know about previous owners. It currently has 140,5xx miles. I have had it since 110,000.

In reading trying to make sense of the "misfire on all 4 cylinders" code issue, I have found a number of maintenance items which are tempting to me. However, I would like to get some opinions from the experts before making the 'parts-plunge'. Below is a video of my car at warm idle and slight revs. It's a bit louder because the downturn I have for Auto-x is currently on in place of the stock split and mufflers and I took this in a parking deck, but perhaps that's a good thing because it's easier to hear. I post this because it seems from what I've read here that the "puff-puff" or "popping" noise from the exhaust could have to do with the injectors. Popping noise is the most apparent past halfway though the video.

[media]http://www.youtube.com/watch?v=aVuXsnDLowY&feature=share&list=UUiw66KUzoS p7CrR_F62Agpw[/media]

I am mainly trying to figure out if these codes are a cause for my concern, and if so how immediate the issue is. I have been considering pulling the valve cover and doing AP2 retainers/keepers, valve adjustment (I have not done this since buying the car), injector cleaning, and valve cover gasket. Is this reasonable given my situation?

Threads I have read on this issue:
https://www.s2ki.com/s2000/topic/817...-from-exhaust/
https://www.s2ki.com/s2000/topic/659930-misfire-thread/
https://www.s2ki.com/s2000/topic/292...all-cylinders/
https://www.s2ki.com/s2000/topic/569...head-in-place/

Apologies for the long post, but I like providing all relevant details up front.

Thomas

 

Bump, ordered AP2 valve spring retainers and keepers, valve cover gasket etc, low-mile AP1 valve springs, and new coil packs. Code still hasn't returned. Any input?