Maybe the hose between the breather tower and the throttle body boot has
collapsed ... or collapses when underway.  It's worth a check.

I did a "Temporary" fix on one of mine several years ago (it's still
temporary ... LOL).  I removed the soft hose and inserted a length of
stiff clear tubing to keep it from collapsing.

Mike

Allan Streib wrote:
> I've noticed that every time I check my oil, the dipstick has been
> pushed out about half an inch or so from the fully-seated position.