firing/working on all cylinders

fire on all cylinders

1. To have all cylinders in an engine functioning. There's something wrong with my car—it's definitely not firing on all cylinders.
2. To function or operate at the most desirable or greatest possible level of efficiency, speed, or productivity. (Usually used in the continuous tense.) The new website will be firing on all cylinders once we get the comments section up and running! I only fire on all cylinders after I've had my coffee.
See also: all, cylinder, fire, on

fire on all four cylinders

To function or operate at the most desirable or greatest possible level of efficiency, speed, or productivity. (Usually used in the continuous tense.) The phrase alludes to the cylinders in an engine. The new website will be firing on all four cylinders once we get the comments section up and running! I only fire on all four cylinders after I've had my coffee.
See also: all, cylinder, fire, four, on

work on all cylinders

1. To have all cylinders in an engine functioning. There's something wrong with my car—it's definitely not working on all cylinders.
2. By extension, to function or operate at the most desirable or greatest possible level of efficiency, speed, or productivity. (Usually used in the continuous tense.) The new website will be working on all cylinders once we get the comments section up and running! I only work on all cylinders after I've had my coffee.
See also: all, cylinder, on, work
Farlex Dictionary of Idioms.

firing on all cylinders

 and hitting on all cylinders 
1. Lit.
 [of an internal combustion engine] having all its cylinders working and thus providing the maximum amount of power. The old car is firing on all cylinders despite its age. This thing's not hitting on all cylinders.
2. Fig. working at full strength; making every possible effort. The team is firing on all cylinders under the new coach. The factory is hitting on all cylinders to finish the orders on time.
See also: all, cylinder, firing, on
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

firing on all (four) cylinders

working or functioning at a peak level.
This expression is a metaphor from an internal-combustion engine: a cylinder is said to be firing when the fuel inside it is ignited.
1998 Entertainment Weekly Even when his imagination isn't firing on all cylinders, Amis is still worth picking up, if only to enjoy the jazzy rhythm of his prose.
See also: all, cylinder, firing, on
Farlex Partner Idioms Dictionary

firing/working on all ˈcylinders

(informal) using all your energy to do something; working as well as possible: The 24-year-old player feels that he is not yet firing on all cylinders.
See also: all, cylinder, firing, on, working
Farlex Partner Idioms Dictionary
See also:
  • fire on all cylinders
  • work on all cylinders
  • run on all cylinders
  • hit on all six
  • hitting on all cylinders
  • hit on all cylinders
  • fire on all four cylinders
  • on wax
  • if it ain't broken, don't fix it
  • if it isn't broken, don't fix it