Found this inside the passenger side valve cover on an 05 f150 that runs like garbage.

Any ideas what this is?

 

That's the valve retainer, where is the dropped valve? Probably killed a cylinder.

 

If your talking about that little half moon tapered piece on the end of the stick........... it looks like a valve keeper.. That is what holds the spring onto each valve.. takes two of them to make a circular LOCK.

 

I think we know why it runs like crap!

Like 399gashog said, that's a valve retainer/keeper, or at least half of the pair. When you say it "runs like crap" what are you describing?

 

Probably loud clanking sounds and a limp?

Hopefully he just found the retainer and not the whole tool in there.

 

video on how to install keepers.

 

Well that explains some things.

I'm not a mechanic, but an hvac tech that works on the work trucks when we're slow.

This truck started missing severely and threw misfire codes for cylinder 1 and 2, plus random.

After testing the coils, I found cylinder one's spark plug smashed. A previous person had broken a plug in that cylinder, so I thought the impact was from that.

I figured the problem was in the valves, but management wanted me to run through many different tests before I called it lol

Ended up testing vct's and fpdm before deciding to pull a vct and inspect it. That's when I saw that keeper.

Thanks, trucks going in for some major work.