Fuel injector pintle cap

[EvilTheCat]

Does anybody know what these caps are actually for?

While cleaning my injectors during an upper plenum gasket replacement, I noticed one was missing.
I put the injector back in and found the stupid cap in my rag while cleaning up after everything was put back together.
Too late.
My truck runs great, so I'm not too worried about it.

I found out that they are called pintle caps, and on other forums people don't seem to think they're needed.
I just want to know what it's actually supposed to do.

 

[colintrax]

Probably help with the spray or atomizing (how ever you spell it) the air/fuel. Guess it's up to you whether or not its worth putting it on, I personally wouldn't have put it back in without one. But that's me