2008 Range Rover Sport HSE 4.4 Cylinder Misfire on all 8 cylinders P0300 - P0308

Crank my truck up one cold morning and it went dead. I thought nothing of it crank right back up no problem. Let it warm up and went about my day as I was accelerating I could feel a slight power decrease no matter when I hit the pedal at any speed it would drag a bit. I was thinking maybe its time for tune up so I purchase a scan tool just to see if any codes were stored. There is no check engine light on but when I ran my launch VIII it shows 12 codes. P0301 - P0308 cylinder misfire, P0300 - Random misfire detected, P0316 Misfire detected on startup, P0420 Catalyst system efficiency below threshold bank 1, P0430 Catalyst system efficiency below threshold. Bank 2. I’m by no means a mechanic but can pick up things quickly and have some knowledge with engine. My thought was this is probably a fuel issue causing my misfire issue. I have a fuel diagnostic tool but not sure where to connect on this engine as I can’t fineSchraeder Valve to check fuel pressure. Since the vehicle runs somewhat well could it just be that I need to relplace fuel filter(where is that located)? Just was hoping someone could help in pointing me in the right direction.

Do anyone know where I can connect the fuel pressure gauge to test fuel pressure on this vehicle? No valve

Not familiar with that vehicle but if it doesn't have a schraeder valve then you need to tee into the fuel line at filter or rail.

Thank you for your response. I’m not sure where the fuel filter is located. I’m guessing it’s in the tank. I do see a rubber hose that connects the two rails so I’m thinking I can Tee into that line.

Fuel filter appears to be in tank assembled within fuel pump or near it.

imgur.com/a/OJ2aPOS

Very much appreciated. The diagram helps a lot. I don’t have the special adaptor but I think I can figure out something to connect to at least one of those spots in the fuel rail. Just my luck fuel filter is in the tank. Might as well replace both if I have to remove tank to access it.

I think this one of the area’s in the attachment but not sure how to remove I can realease the casing around the area but after that it seems to be springy. Just wonder if anyone knew what this was called so I could Rea search it.

www.amazon.com/OTC-7337-Fuel-Line-Disconnect/dp/B0002SRCYW

imgur.com/a/raOauM5

Video on removal:

I'm researching just as you I never see these before.

You could probably make a tool yourself... measure diameter, find a pvc pipe that fits and cut like this and reassemble on fuel line lol

imgur.com/a/Cfo6WYc

okay don't cut like that, cut it in half instead to make fitting it on easier

I have been checking everything on YouTube and did not come up with anything. Thank you for your research. Going to try to go at it tonight.