The car runs fine but the valve train is making a ton of noise at idle and between 3-4k RPM in any gear under load or just revving in the driveway.
I took the car apart to put new plugs in (have to tear apart the cowl and everything else to get to it easily. So I took the upper intake runner off and adjusted the valves while I was at it. The intake valves were all within spec but the exhaust I couldn't even get a feeler of any size in there. Made the proper adjustments and the car runs way better but is still making that god awful noise. It almost sounds like a bad lifter on a LSx motor. One of the plugs looked lean in the #3 cylinder and I'm deducing that it's either a bad injector, coil pack, or an actual lifter.
Any recommendations?
2010? Lost motion recall. Verify its been done post haste.
I verified that it was done before I cracked anything open. Forgot to mention it was one of the first things I checked when opening the valve cover. I can't believe they made the valve cover and spark plugs such a pain in the ass to get too on this car.
I tried fit freak.net too no help at all searching through threads and even posting.
Fit freak is the most useless forum I have ever belonged to. It's a bunch of hipsters getting their rocks off to tucking wheels and shaving their sweaty man-ginas.
Has the noise increased recently, or is it making more noise than other Fits? Are you sure it's not just the typical Fit engine clatter? Maybe it's obvious in person, but it's worth asking. I know I had read that adjusting the valves was known to quiet some of the clatter on these engines, and when I did mine I had to tighten the clearance on every valve to get it into spec...But it still didn't really change anything as far as I could tell. It seems to just be a clattery little engine that otherwise runs like a champ. Other than that, I suppose that now would certainly be the time to replace coils while you're in there. But off hand, I don't recall injectors or lifters being known weak points on these engines. So I'm not sure how far I would go with all of that either.
Then again, I generally don't overcompensate with unamusing stereotypical criticisms...So what do I know? 
In reply to Driven5:
Wanna talk about it champ?
I do, however, agree with johnny5 here. The fit makes plenty of noise, especially when you roll up to a stop sign, or lift off the gas. The engine has DFCO. (That's decelerative fuel cut off) The injectors are what's making that noise. Or so im told, by hipsters tucking wheels 
Do you have a mechanics stethoscope? Put it on the fuel injectors and see if that's the source of the noise. My ls400 had noisy injectors and that was the only part of the engine you could hear running with the hood closed. ;)
I don't have them but still have plenty of friends that are dealer techs that I could borrow from.
I had a 09 Fit when they first came out and don't remember the noise but I also only put 20k miles on it before I ditched it. If it was more consistent through the revs I wouldn't think anything of it. The fact its just at idle and between 3-4k rpm makes me scratch my head. Almost like a diesel engine. I just installed a new stereo system and a cold air intake on this thing. Maybe those will drown out the noise with some 15w-40
Obviously I can't hear it so it might be unusual valve train noise that needs addressed. Hard to say from here.
If I had something that could record decent audio I would upload it. I am still too cheap to upgrade from my 1st gen GoPro which no longer records sound and bought a $25 Amazon dash cam to replace it with.
Car feels much better after the valve adjustment though. Like I said I'll likely just toss in some 15w-40 and deal with it until I decide to trade it and the S2K in for a CTR in a year lol
My Civic uses an L series 1.3 (so close to yours) and the valve tapping is the loudest I've heard in any car. But it's been doing it nearly 200k miles, and it just seems to be normal for them.
I have had my '13 since it had 12k miles (now at 32k) and I've noticed the same chattery sound at idle. I think it is just the engine. I'll be cracking mine open early to do the valve adjustment just in case, but it's always been that way.
I threw an HPS short ram intake, 15w-40, and some component speakers in it today (to aide the new head unit) and can't hear that noise anymore. It runs great, that noise was just more of an annoyance than anything. After thoroughly inspecting the valve train and knowing nothing is wrong and the valve springs are in spec, I feel fine. Got my hands on mechanics stethoscope and will be diagnosing the injectors tomorrow, also got a few extra coil packs from the same friend that lent me the stethoscope but he thinks they are bad, worth a shot. I also finished up my retrofit of the headlights.
Wonder where that vibration was coming from?
