1999 Toyota 4Runner engine

Hi
Am hoping you can provide some insight. Had this problem for a while, and have not found anyone with a diagnosis yet.
There is a vaccume line that runs from the right rear of the engine to the intake system (runs into the assembly that goes from the air cleaner to the carburator). What is happening is that oil is being pulled into this assembly (ultimately being deposited not only on the carb intake and attatched parts, but building up in the vaccume canister assembly, enough so that over time, I would have an overflow of oil running down into the air cleaner.) We thought we had a blown engine problem, was even diagnosed as such, but perodicly taking the stuff aprt and cleaning up the deposited oil has elimated the "oil on the driveway" problem. However, the "chk engine" light still comes on frequently, and the only way I know to stop that is to disconnect and then reconnect the battery cables (reset, I guess) I have changed out the PCV valve, and when I pull that vacumme line, I do seem to be getting "some" suction at the above mentioned vaccume lines connection point (to the right rear of the engine.
any insights?

Thanks
Nick Young
(Nickoli2@cox. Net)