:My latest theory is that, while I was under the car doing an oil change and the oil cap was off above, it flew into the crank case, and eventually worked its way through the system to end up there. Or maybe while we worked on the engine the last time, it flew into an uncovered part. But we're pretty good about keeping things covered.
To get to the restrictor, oil *should* have gone through the filter to get there. When the engine is apart there's all sorts of ways for this to happen.
