The car has 145000 KM, never had any major issue until a few days ago.
I was driving suddenly VSA + Engine Light comes on. Limped home and checked OBDII. Problem was Low Oil Pressure switch, checked oil level which was super low. Did an oil change and noticed 2L of oil was missing (never had any issue with oil burning or leaking. I checked around, no signs of oil leak or burning.
Exhaust looks good, Spark plugs looks good, Coolant is nice and clear.
Reset engine line and everything worked.


Then for the last two days
First thing i start up the car, VSA + Engine Light comes on, car vibrates a little.

OBD Scanner Shows:
P2647 Rocker Arm Actuator System is Stuck Open
P0305 Cylinder 5 missfire

Spark plugs looks worned, will replace it.
Coils resistances showing 1.8Kohm, swapping them makes no differences.
Any suggestion would be appropriated.

Thanks!

 

Solved both codes last night. I'll give details so it might help others in the future.

Cylinder 5 missfire was fixed when i swapped 6 new spark plugs.

Rocker Arm Actuator code was much more difficult. Basically the VTEC solenoid/valve/pressure switch is not functioning correctly.
I followed procedures from the following threads + service manual:
https://acurazine.com/forums/2g-tl-problems-fixes-117/oil-pressure-switch-location-813015/
https://acurazine.com/forums/1g-tsx-problems-fixes-128/seized-vtec-solenoid-symptoms-causes-solution-pics-879805/
Service Manual Page: 11-220, 11-221, 11-226 & 11-227

First i unplugged the 1 pin VTEC solenoid valve wire and tested the resistance from pin 1 to the body of the valve. It was about 18ohms, which was within range (14 - 30 ohms).
So it appears the VTEC solenoid valve is functioning properly.

Next thing the service manual recommends is to check the entire assembly. This requires removing 3 long bolts holding the assembly and the oil filter. I found that all three bolts can be removed from below the car using ratchet + extension (Remove the plastic side cover to allow access to the 3rd). I tested the valve's play and everything seem just fine. Filter was cleared no clog anywhere. Upon closer inspection i found pieces of blue glue stuck within the valve's spring and assembly. I removed all the pieces and put everything back. Soon as i start the car both engine light disappear and the car run smoothly again.

I looked around the car and found traces of the glue (i think) being used to seal two pieces of the engine together, whoever did it must've used too much and pieces fall out over time.

 

Im getting a P2647 too, just happened today. I just installed a supercharger yesterday but I have no idea how the two would be related. I tried clearing the code, it just came back as soon as I started up, I disconnected the battery for a while, still came right on. I took off the assembly to inspect it, it looks clean as hell, nothing in the screen or in the spring in the housing you talked about. The shaft moves up and down fine... I dont know, Im gonna put it back together and see what happens. Im confused as hell. I have a damn misfire code to figure out first of all, and now this bullshit. Thanks for your info though, it did help me out

 

bookmarked for future info thanks for sharing!

 

Yeah i took care of the misfire code first. New spark plugs did the trick. Make sure you torque it according to spec!
How many miles are on your car? To make you feel better mine has started burn oil after this whole issue, its going through 1qt of oil every 1000mile.