Billman250

If its an 05 you don't have broken retainers.
I can assure you if the valves were never done, that is not your problem either. Coil packs are likely not the problem either. Cam chain tensioner will not fix your problem that's a fact.

Billman250

If you are lucky, that scanner can read live data. Particularly, fuel trim. This will tell you if a rich or lean condition is causing the misfire.

If you are getting a cel and cannot feel a dead misfire, fuel trim is your first diagnosis step. That is also fact

solidol

So many facts very cool.. so in regards of tensioner and valves - I just want to do it because it feels too noisy..
I can see live data.. I think it makes a snapshot when for every registered error. Not sure will check.
I verified it's not spark and so if it's fuel delivery and only 2/4 then can't be fuel pump and probably not a fuel ramp but injectors..

//thanks for helping out

suzawadc2

kinda doubt the fuel pump. USUALLY when fuel pumps take a crap the don't work at all. i've seen some (i'm a tech a honda dealer) on 02- 06 crv's where the fuel pump wasn't putting out the sufficient volume of fuel where it results in a low idle and lack of power. i haven't seen a s2000 yet with a bad fuel pump

if your scanner can read the MAP sensor voltage, then you can tell right off the bad if it's mechanical or a electrical causing the misfire dtc. if MAP sensor voltage is 1.0v and higher, then i would suspect a mechanical issue (1.0v and lower is good) then, i would visually inspect the valve train and check the valve lash

i would rule out the chain and tensioner. if your tensioner and chain where faulty, you would DEFINATELY hear it. kinda sounds like a flutter as if you had a baseball card flapping in bicycle spokes. also, it would affect all cylinders not just 2 and 4. you would probably have misfire codes on all cylinders

solidol

Thanks. I think I've seen misfire in 1st cyl before I swapped coils.. but 3rd is always good.
i'll check map sensor voltage but it's funny it started happening once I put ngk spark plugs and changed oil before the trip. Though now it happens with densos too... it just funny because it feels like I disturbed the engine which was in good standing but now is messed up will report back on v range

suzawadc2

make sure you check MAP sensor voltage when vehicle is normal operating temp @ idle.

solidol

I couldn't read voltage but pressure only with my scanner. There is way to customize live data params but I didn't take manual with me and can't find that menu. Will check once back home. So 2/4 came up again when just cruising.. with the snapshot I got it seems like it happened when sharply off the throttle. Engine load was like 25% and rpms ~870..

Will hookup multimeter to the map and see what’s there. It's Easter tomorrow so it would need to wait for Mon..
I'm sure sparks and coils for those two are fine.. it's either injectors or valvtrain.. otherwise it would be spread across four cylinders

solidol

wasn't driving for two weeks due to traveling but last time cel was coming up quickly in 2nd/3d/4th but never @1st; under different conditions and load.
didn't get to map but just checked valves - gap was fine except one exhaust and one intake on 2nd cylinder.
need to go to pick up some stuff right now but I have a feeling next I have to clean injectors/fuel tract

solidol

not really - it went away just as quick as appeared. All I did was adjusted valves and used antiseize putting spark plugs back in.
I can't really explain but it's gone for last 500 miles or so. Heading to Yellowstone for Memorial weekend and so will see how it goes