Why are there holes in the cross hatched area of an oil dipstick?

[Thermo1223]

It's been proven that the amount of detergent remaining in a motor oil is directly related to the surface tension of the fluid. Therefore, the manufacturer puts tiny holes in the dip stick so you can test for remaining detergency by simply blowing on the dip stick as shown:

View attachment 134472

I'm believing this as truth from now on and telling everyone I can. You can't lie to me anymore *insert auto maker*.

 

[leadcounsel]

These holes were punched out due to Congressional action, in Public Law #25830 of the 197th Congress, signed into law in 1993 by Bill Clinton, for fuel efficiency standards.

Much like bakeries that sell "donut holes," there are automotive shops that gather and sell all the unloved "dipstick holes."

 

[FowVay]

I'm believing this as truth from now on and telling everyone I can. You can't lie to me anymore *insert auto maker*.

Be certain to include the picture. It needs the picture for visual effect.