Basically was doing knock sensor in ls1 camaro 98. Uhhhh when putting back the manifold I Think I dropped some plastic peice proavably 2 cm long a cm wide into the far left hole under the manifold. I’m not 100% if I did but I think I did. I don’t kno what those holes are called but it definitely ain’t good.started the car. Sounds fine... What do I dooooo

 

Pull the intake back off and get it out of there.

 

...If you started it then its possible it was pushed into the cylinder burned up and sent through the exhaust. Or its hung up at the moment and will rear its ugly head somewhere down the road like maybe getting stuck in the ring land of the piston which could have damaging consequences. If its running without issue you can either tear back into it in an effort to search for this mystery piece of plastic or leave it alone and hope for the best.

 

UHHHH, i drove it for 30 min, knock sensors were good. Nothing exploded yet. I don't really know. Thx for reply

 

Not in the intake, somewhere in the block I think

 

I wouldn't sweat it at this point

The holes you speak of under the intake manifold are the intake runners on the cylinder heads. These openings lead right into the cylinder bore once the intake valve opens to let the air/fuel mixture enter for compression/combustion.