That's really surprising. I would expect the cam lobe to be just as bad as the fuel pump appears.

That's what I expected, but it looks good. Went for a test drive and everything seems normal again. 🤷

This failure was due to not having the gasket installed. The gasket is somewhat thick, so I think this sat lower than it should have which caused all this damage to the follower. Idk how the person who installed it missed the gasket...I brought it in specifically FOR gaskets and tensioners, but whatever. I'm just glad this chase is finally over...for now.

Those gaskets are meant to be replaced every time you remove the valve covers along with the two o-rings on the fuel pump studs. They are very thick!

Having same issues on my ISF. Car feels restricted under WOT. I have PPE UEL Headers with Reflash RD base map (car was misfiring like this on stock headers aswell). Misfire Cyl 5 at 4500-5500 rpms mostly at the top of 5th gear. I’ve done compression test & all checks out well. Also did leakdown test no leaks. I’ve disassembled intake manifold replaced all gaskets and seals new PCV resealed Valley Plate etc. Pulled DI & PI Injectors replaced DI in cyl 5 and cleaned and resealed the rest of them. Boroscoped all cylinders and don’t see any scoring etc. oil changes have always been done at 3500 miles with penzoil ultra platnium. BG44k every 3rd full tank. Still issue presists. I’ve done live data logs and it shows cyl 1 3 7 all misfiring very slightly upon WOT but not enough to throw a code but time over time cyl 5 always gets that one misfire that throws car into limp. Other then that car starts perfect runs and drives perfect just WOT its restricted. Honestly lost for any ideas, going to check live data and see what Fuel Pressure PSI should he at WOT. If anyone knows or has had this issue before any help would be appreciated thanks!
2008 Lexus ISF 163k miles. Plugs have been changed btw 10k miles back with NGK & Coilpacks were done aswell.

The NGK plugs were after the problem started?

I would suspect the fuel pressure sensor at this point.

no car ran fine after plugs were done. Would the fuel pressure sensor throw any codes?

Not necessarily. The FPS can be unstable but not set any DTCs.

I'm asking about the plugs because I've had a bad experience with plugs quickly dying at higher rpm despite being quality units from a reputable source.

Many plugs are counterfeited and die fairly quickly. Where did you get yours?

well then i guess i am taking that manifold back off again sucks but i really miss the top end on these cars. So the sparkplugs i did them at 150k bought them through advance auto like i always do for denso or ngk plugs. I even checked the gaps and they were correct car currently sits at 163k and turning. When this issue first happened I replaced cyl 5 sparkplug again but misfire continuously showed up. Not sure if i mentioned it earlier but i also tried a new LPFP deatschwerks unit so i could eventually run full E85. Issue still persist. It’s weird because sometimes it’ll get all the way to 7200rpms no issues and sometimes it’ll feel as its getting caught up and getting held back around 4500-7200. Another thing to mention is that the misfire counter shows misfires in only cyl 1537 never in 2468.

yessir both have been replaced upon getting the codes p0012 & p0020 CEL has yet to come back for those assuming it is good. I’m thinking a faulty ECU ?

If that's the problem, it might be difficult to fix.

I'd try ordering some new knock sensors and installing them. If you get them from Japan (Amayama, Megazip, etc.) they're pretty cheap. Less than $20 each. I have four new ones to put in when I replace my fuel pressure sensor.