I've had a slow oil leak for about 6mos. Over the weekend I went through 2 quarts of oil in a 20 mile highway drive. When I got home there was a large puddle under the car. I'm thinking the seals need to be replaced, however the mechanic has just finished looking at it and said I was "missing" 2 camshaft bolts... causing the leak. Does this seem possible? He has ordered a seal kit and will replace for $300 if I'd like (no brainer, of course I'm having done). But, since new bolts it's stopped leaking!!! Has anyone heard of such a thing? How would 2 bolts disappear???