Is it just snake oil or does the stuff work !?

[AntMan201]

I really do try and do my research before asking or posting, and it looks like both Seafoam and MMO are both highly not-recommended on these forums for the 5.4

so I did more research and found these videos from someone who did incredible research and tests on both and the results blew me away. Considering he’s an unbiased source, would it be good to take his advise and give it a shot to see if they help something that honestly isn’t really broken ?

the only reason I’m considering is because cylinder 8 keeps misfiring even after changing both spark plug and ignition coil (all 8 motor craft via Rockauto) and I spent like $300 for everything.

Maybe carbon build up ? Anyways, I’d love to hear some opinions even after watching the videos.

Seafoam here

Marvel Mystery Oil

 

[Hamfisted]

What's left, electrical connections to the coil or injector, or the injector itself ?
I don't think either do too much in a 4 stroke motor. What I found to work well was either Amsoil Power Foam (online) or CRC Intake cleaner (Advance Auto), sprayed through the throttle body butterfly with the engine at about 1500 rpms. Empty the can into the throttle body, shut the motor off for 15 minutes, then drive it. When I disassembled my motor I found the intake valves to be pretty clean, but there was a lot of soot can carbon debris on the intake runners and intake ports, not much on the valves or on the chamber of the heads. I think the other stuff works better on 2-stroke motors though.

 

[Ozzy]

I seem to recall a video done by Fordtechmakuloco that dealt with a phantom misfire, where #8 misfire was actually caused by #1 or vice versa. I tried a quick search but didn’t find that particular video. I did see one that wound up being #4 misfire caused by bad seating of injector #4.

Just tossing that out there. May not apply to your situation.


Sent from my iPhone using Tapatalk

 

[Quadmaniac]

Not really snake oil - I have used Seafoam to free up an intake valve that was stuck open due to carbon deposits on the stem (on a 2004 Ford Escort). I also use it often to self-clean the jets in many of my old desert quads... It is not, however magic. It works in limited cases but I doubt some of their grand promises.

However, it is cheap and doesn't cause harm, so it is certainly a viable option as a last resort! Just don't hold your breath.