installed CAI last night, and test drove about an hour.
after came back from test drive i notice that air fillter was fall off from its location. so i put'em back in.

is it going to be a problem? or cause any problem to an engine?

 

OMG...don't let the air filter come off! It probably didn't do anything, hopefully...?

Depends on where your filters located. Just look at it this way, imagine a 3" vacuum cleaner hose sucking in or up debree. Ever look in the vacuum bag or canister? That's the same stuff your engine will be choking on!

 

Ditto, not god but there isnt a way to see what you sucked up , TRADE IT IN.......J/K