One out of the 6 of my
Toyota Tacoma cylinders is mildly leaking, as indicated by a
cylinder leakdown test. While other cylinders are leaking only something like 5-10%, this one leaks about 20% of the pressure that goes in while the cylinder is in TDC.
I also lose about 2 qt of oil each 1000 mi or so. I think the cylinder leaks because when I did a tuneup and head gasket change last year, I rearranged the valve tappets to meet the clearance specification and one of the exhaust valves on that cylinder was slightly off and I didn't want to wait a week to order a correctly sized replacement. Therefore, the cylinder is probably not sealing tightly.
Can it be that oil is getting into the combustion chamber because the valve is not sealing tightly?
Other than losing oil, the truck runs great. The only noticeably consequence of the oil loss is that I have to spend money on refills between changes but there is no mechanical malfunction.