Based on your explanation(s), I think your engine is burning oil; it's just that you're not able to see the blue smoke coming out of the tailpipe. Try driving city streets at night where the headlight of any car behind you might illuminate the haze from your tailpipe. Or drive the car at an expressway speed for a few miles, coast to a slower velocity (about 30 MPH - as if you're slowing down on an exit ramp). Then accellerate strongly. This may enhance any smoke coming from the tailpipe due to the extended higher RPM at zero throttle. The goal is to create the most vacuum within the engine for the longest period of time. You should have an overdrive button on your gearshift. Turn the overdrive off to force the engine spinning during your exit ramp.
I discourage the valve cover (gasket) kit. The quantity of oil you describe - - if it was leaking past the gasket(s) - - would be leaving the engine block soaked with oil. Your floor would be a slippery mess. Either that, or the oil would be dripping onto the exhaust manifolds and making lots of smoke under your hood.
Examine the snorkel hose running from the air filter to the throttle body. If the inside of that accordian-looking hose is saturated, you may have found your problem. Lots of oil in that area indicate excessive blow-by in the crank case (worn piston rings). The oil vapor created by all that piston/crankshaft activity inside the crank case is being pushed out of the crank case area and sucked into the intake chamber(s) via the connecting hose (from the valve cover to the snorkel hose).
Make sure your PCV valve is functioning correctly. Or just replace it. They aren't that expensive. A faulty PCV valve stuck in the open position allows the engine to suck in too much air from the crank case (as well as the oil vapor suspended within). You may have a check-engine light for a "Lean" code, as well.
A stuck closed PCV can cause the opposite effect, where too much blow-by and oil vapor is sucked into the intake stream as explained in the previous paragraph.
Finally, check your spark plugs. The three up front by the radiator are easy enough to get to. The ones in the back are more challenging. But, check for signs of oil accumulation on the plugs.
Tuesday, February 17th, 2009 AT 7:37 PM