T da B

Good idea on the compression test. I'd also ditch the Mishimoto sandwich plate pronto. I ended up returning mine after I noticed oil leaking out from under the filter, even after way over-torquing the oil filter. I had suspicions that it would happen after inspecting the mating surface. The stock oil cooler/heater's mating surface is perfectly flat and polished to a mirror shine, but the surface of the Mishimoto is rough anodized aluminum--far from a mirror polish. I ended up getting a Mocal sandwich plate, which doesn't leak. Still have to over-torque slightly as the surface still isn't perfectly flat, but it's better than leaking oil. Hope you figure out your issue!

SpitfireS

Are you sure all the vtec parts are as they were?
All those little pistons and such.
None of them dropped out of the rocker assembly while removing them?
And if they did they went back in as they should?

IOW: are you sure the whole valve train is 100%?

ericmdub92

We did have a pin fall out while moving the assembly however we quickly replaced it in its correct spot. We had some trouble getting the assembly to sit flush (we had to lift all the arms before setting it down) and pins moved about then but we always pushed them back in to the correct spot.

To reiterate the original post we also took a look at the VTEC solenoid and everything looked 100% there but we also cleaned it out for good measure.

I'd imagine if a VTEC pin were incorrectly placed/put in that I'd be unable to be in VTEC in any of my gears/the issue would rear its head during all VTEC use and not just when I'm in VTEC for an extended period of time in a high gear only... I'm no expert though, just offering a counter point

twohoos

I'd double/triple check the VTEC solenoid, including the solenoid gasket(s) - ideally swap in a known-good assembly.

If that doesn't fix it, it sounds like an oiling issue. VTEC engagement (including remaining in VTEC) relies on oil pressure, so something must be clogging up the VTEC oiling path, or somehow losing oil pressure during long stays in VTEC.

ericmdub92

Compression tested the cylinders and everything looks fine/engine looks healthy

Cyl 1 - 221 / 222
Cyl 2 - 220 / 225
Cyl 3 - 235 / 240
Cyl 4 - 235 / 238

Here are some pics of the spark plugs - they were added about a month ago, around 800 miles since they've been added... does anything look wrong?

ericmdub92

ericmdub92

Also my new coil packs came in the mail a day early, going to try those

ericmdub92

rechecked all gaps on spark plugs and they were fine
re-torqued all plugs to billman spec
put new coil packs


test drove the car around and drove quite a while but finally got the issue to occur during a the top of 3rd gear (~8k rpm) again. still the same mysterious flashing CEL and pending p1399

going to clean injectors as a last ditch effort then throw in the towel

SpitfireS

The outside temps were lower at the time?
It could indicate it's 'oil related' as it took more time to really heat up & thin out the oil (you're not using a dino 20 weight.. are you - I had to ask)
I said 'oil related' as it still can be a 'vtec leak' as thinner oil can't keep vtec up or something.
The other code P1259 never came back?
And you don't notice anything righ before the cell pops up (I know that's not easy to do)
Do you reset on the spot and do another run / test or do you limp home and reset at home?
I don't know what happens if just one set of pins is in the wrong order - there are 2 lenghts of pins - if the ECU will detect it straight away, in or out of vtec.
As far as I know the ECU detects missfires by looking at the crank sensor signal, looking if the signal is steady during crank rotation.
Maybe even in combination with the cam sensor(s), I forgot if we have a sensor on both cams.
So you could say:
(1) There really is a problem in vtec.
(2) The ECU looking at faulty sensors THINKS there is a problem in vtec.
Is the ground connection at the back of the head ok?
I donno...

ericmdub92

Just wanted to post an update to this... i have an appointment booked in the beginning of july with evasive, hopefully it'll all get sorted then.

in the meantime i realized that my issues seem very similar to those of people with MAP issues... e.g. https://www.s2ki.com/forums/s2000-un...ng-out-640530/ and https://www.s2ki.com/forums/s2000-un...6000-a-581814/

im going to try the map whack and add the zip tie/housing to secure the MAP sensor.
also going to clean the injectors while im at it

these are my last attempts... dont want to cause any more unnecessary damage (if i am causing any)