Its your chain oiler pin. Search it, Both Cliff and I had that happen on our VE motors. Its very common for whatever reason on the VEs probably due to higher oil pressure. Yes you need it to be in there. You will have to remove the front cover/oil pump to reinstall it. Drop the pans, remove crank pulley and belts, Remove pickup tube and then remove the front cover. There is a little dot on the front face of that piece, Needs to be reinstalled with the dot pointing straight up in the 12 oclock position. Put some loctite Red or 252 on the part that goes into the block and gently tap it in until it seats all the way in. Give it 24 Hours to fully cure before starting it back up. I can gurantee it wont pop out ever again after that. Mine was fine and i use a 15w50 oil that sees higher pressures than using a thinner oil..