put a (monkey) wrench in(to) the works

put a (monkey) wrench in(to) the works

To disrupt, foil, or cause problems to a plan, activity, or project. Primarily heard in US. We had everything in line for the party, but having the caterer cancel on us at the last minute really threw a wrench in the works! It'll really put a monkey wrench into the works if the board decides not to increase our funding for this project.
See also: put, work, wrench
Farlex Dictionary of Idioms.
See also:
  • put a spanner in(to) the works
  • put/throw a spanner in the works
  • throw a monkey wrench in(to) (something)
  • throw a monkey wrench into
  • throw a spanner in the works
  • throw a spanner in(to) the works
  • throw a wrench into the works
  • throw a (monkey) wrench in(to) the works
  • throw a monkey wrench in the works
  • put a spoke in someone's wheel