Cadillac Repair: engine joil consumption, oil filler cap, fleetwood brougham

Question
I have a Cadillac with 4.1 engine RWD 83 Fleetwood Brougham. Engine runs rough when first started, probably needs fuel sensor or ecm.  But worse it uses quart of oil roughly every 500 miles.  No smoke, no noise and seems to run normal after warmed up.  I also suspect the vacuum line coming from the intake manifold is carboned up.  Does this engine have some type of filter in the area of the intake and if so could the intake being carboned cause the engine to use oil or does it obviously need rings, etc. Thanks for you evaluation.  

Answer
Hi Floyd, That sure is alot of oil for not seeing any on the ground, outside of the engine or blue smoke from the tailpipe. The pcv valve is a possability for oil consumption if it sticks open and is real easy to replace. Just look in the valve cover. Also the intake manifold bolts have a tendency to loosen up and if you remove the oil filler cap you can stick a 13mm 1/4" drive swivel socket on an extension into the cover and try to turn a bolt. They should be tightened to about 24 lbft so if you can turn that bolt the gasket needs to be replaced. The rings still could be bad or the valve guides worn but fixing the obvious leaks is the first thing to do. If the rings are carboned up GM engineers recommend removing the sparkplugs and pouring 4oz of top engine cleaner into each cylinder and letting it soak for at least 8 hours. Then with the B+ wire at the coil disconnected crank the engine to remove the excees cleaner, then install the plugs and plug in the B+ wire. Start the engine outside and then drive it for awhile until it stops smoking, boy will it smoke, and then get the oil changed. This procedure helps with stuck rings on the northstar engines too. Hope that helps. Bill