What the hell is a misfire?
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Soldato
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Enfield said:
How can you tell its not running on all cyclinders? apart from it feeling and sounding crap!
Soldato
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Enfield said:Well if you can't hear it, you're blatently deaf and if you can't feel it then well you're a vegetable
Just wondering if there was a more technical way of knowing instead of just going by my senses
misfire: verb
A misfiring cylinder is not contributing to the engine power output, because the fuel/air mixture is never ignited. It makes your engine sound rough (like a Subaru Impreza
) and you will notice a lack of power, more vibration and dire fuel economy. Depending on the cause it may only misfire under certain conditions, e.g. usualy under load if it's ignition related.
- To fail to ignite when expected. Used of an internal-combustion engine.
- To fail to discharge. Used of a firearm.
- To fail to achieve an anticipated result: a scheme that misfired.
A misfiring cylinder is not contributing to the engine power output, because the fuel/air mixture is never ignited. It makes your engine sound rough (like a Subaru Impreza
) and you will notice a lack of power, more vibration and dire fuel economy. Depending on the cause it may only misfire under certain conditions, e.g. usualy under load if it's ignition related.even worse is that the piston not firing is probably diluting your engine oil as it swills around the bore until its sucked out into your catalist where a stray spark will cause a backfire explosion which will leave your car in 437 assorted different pieces & you will be given a fixed penalty under the new law for deliberate litter dropping
A misfire can destroy your engine in the worst case. It can be down to bad timing such as when my distributor came loose and the ignition became a random sequence 
Most common cause would be worn HT leads, they lead to the spark plugs. Get someone to rev the engine (under load would be better still, handbrake on or something) while you look under the bonnet in the pitch black, you should not be seing any sparks.
carefull you dont hurt yourself, I did this once in the rain standing in a puddle, oww
Most common cause would be worn HT leads, they lead to the spark plugs. Get someone to rev the engine (under load would be better still, handbrake on or something) while you look under the bonnet in the pitch black, you should not be seing any sparks.
carefull you dont hurt yourself, I did this once in the rain standing in a puddle, oww
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Test each spark plug by disconnecting one lead and see if that make is worse ( in which case that cylinder was doing useful work ) or no change ( so that cylinder is waste )
Mind the voltage !
Mind the voltage !
