You kind of have to visualize the end of this joke.
A hot blond was driving her sports car down the road and it just stopped running.
She pushed it into a service station and asked the mechanic to have a look at it.
He asked what happened and she told him.
He said OK, I'll have a look at it.
Within 15 minutes, the mechanic had the sports car humming like brand new.
The blond asked . . . what was wrong with it ?
The mechanic said . . . ." just crap in the carburetor".
The blond asked . . . . . . . . . . . . "How often do I need to do that ?"