backfire

Short definition from Wiktionary

Verb

1. 1
   To fire in the opposite direction, for example due to an obstruction in the barrel.
2. 2
   To experience a premature ignition of fuel or an ignition of exhaust gases, making a popping sound.
3. 3
   To fail in a manner that brings down further misfortune.
4. 4
   To set a back fire (small, controlled fire to limit spread of a larger fire).

Noun

1. 1
   Alternative spelling of back fire.
2. 2
   A premature explosion in the cylinder of a gas or oil engine during the exhaust or the compression stroke, tending to drive the piston in the wrong direction.
3. 3
   An explosion in the exhaust passages of an internal combustion engine.
4. 4
   An explosion in other equipment.