Blowing A Gasket

Figuratively, to blow a gasket is to become suddenly angered. The surge of energy and anger is compared to the popping (blowing) of an automotive gasket, which is a mechanical seal to prevent the leakage of fluid.

When a gasket "blows," there is a burst of fluid. When a person's gasket blows, there is a burst, or an outpouring, of anger for which there was no visible prior warning. Thus, it usually refers to spontaneous anger (without prior planning).

Example: When I read this headline, "Euro soars on report that US ready to aid EU fund," I remarked, "My American friends are going to blow a gasket when they read this!" In other words, they will become spontaneously angered that news reports suggest that Americans will be bailing out European nations (and that someone believes these reports to be true). 


Because I use this as an idiom, I did not alter the idiom for a plural subject ("my American friends"). I did not write, "they will blow their gaskets." I do not believe this is necessary in the case of an idiom; indeed, doing so may imply it is a literal statement, which is not the case. Humans do not have gaskets.