Here we go again P0300+ Friends HG? Fuel Pump/Injectors? Blown Engine

P0300 Mulit Misfire
P0301 P0303 P0304 Cylinder 1,3,4 misfire

Owned it for 3 years
Bought and installed NGK Coils and Plugs from Rockauto less than a year ago
car had been getting worse in terms of burning oil and gas mileage i assumed it was from the winter.

I'm Driving & suddenly car starts to violently misfire. Check Engine flashing. I drive it home at about 50 mph max took 40 mins.

I throw some new spark plugs in. And i see that cylinder 4 spark plug white porcelain has exploded I remove what I can with compressed air and vac, Im assuming its from driving it home. swap #2 plug with #4. Clear codes and it still misfiring exactly the same with the same codes.

When i bought the car 3 years ago cylinder 1 misfired and i swapped an ebay injector in there and had two left over. Engine has been smooth . So i tested the ebay ones i had they were spraying better than 3 and 4 injector so i swapped them. Made sure there was no leaks in the injectors. Still exact same misfire codes even cleaned the plugs.

I remove some oil because i did an oil change recently and i read maybe i put to much oil. Oil seems fine not milky. Get it to about half way mark on a cold engine. I clean out oil inside throttle body cause i see oil. Crank up still same misfire codes and the oil is back in the throttle body. I read this is normal.

did a block test with the car on for 15 mins. Nothing color remains blue. Rented a coolant compression test kit from advance. if i leave it overnight compression drops from 17 to 7 psi. Im not sure if this confirms HG.

I use a cheap boroscope on cylinder 4 and i see a little bit of juice come out as i rotate the crank clockwise. but i only see this happen once the first time. i even rotate the engine for a couple of minutes but i dont see a squirt of liquid again. Cylinder 4 seems to have some liquid in it in general but not much. see attached images.

Im planning on renting a compression test tomorrow as well as purchasing a leak down test. If both those test dont give me anything, then im pulling the oil pan and confirming if a bearing is blown. And im running out of ideas. I plan on keeping this updated please let me know if you see anything im missing

i feel like all i really need are new oem injectors maybe a fuel pump if its not the headgasket. I have ran out of gas a couple times in the past year and the guage only goes down to half and no lower even if i run out of gas.

 

These are 2 and 3 or 3 and 2 i really don't remember. Im not sure i took a pic of one. But 1 looks about the same as 2 and 3 just a little more dry. 2 and 3 also look a little wet.

 

did the compression test on 1 and got around 130 and did 4 and got 10-20. I used the leak down tool to test compression on all 4 cylinders. I turned the engine clockwise on each cylinder until i felt pressure push back against me all of them were strong except 4. 4 had no strength built no pressure. I then poured two caps worth fromn a gallon bottle oil into the cylinder and tried rotating the engine and it was still not getting any push back or pressure building from 4. Im assuming its a stuck open valve.

 

I performed a compression test on cylinder 1 and got around 130 PSI. When testing cylinder 4, the readings were between 10-20 PSI. Using a leak down tool, I tested compression on all four cylinders by turning the engine clockwise until feeling resistance.

Cylinders 1-3 showed strong pressure, but cylinder 4 had no strength and did not build any pressure. I then added two bottle caps of oil into cylinder 4 and attempted to rotate the engine again, but still experienced no push back or pressure buildup.

Based on these symptoms, I suspect there might be a stuck open valve in cylinder 4 that is preventing proper compression. This diagnostic test was performed yesterday.