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.

Common Names:

Name	Pronounced	Usage
Barbara	BAHR-bər-ə (English), BAHR-brə (English), BAHR-bah-rah (German), bahr-BAH-rah (Polish)	English, Italian, French, German, Polish, Hungarian, Slovene, Croatian, Swedish, Danish, Norwegian,
Daryl	['dæril]
Florine	-	French
Engel	-	German (Rare), Ancient Germanic
Apollon	-	Greek Mythology
Balchin	['bɔ:ltʃin]