Jump to content
Mechanical Engineering

what causes an engine cylinder to misfire?

Recommended Posts

In D.I. Diesel Engine - Improper Fuel Injection timing, Unbalanced governor, Defective Injector, Defect in timing gears or chain/sprocket. Burning of oil during combustion through cylinder liner route.
In S.I. Engines - Improper Spark Ignition/Fuel supply. Oil movement to piston through cylinder liner route.

Link to post
Share on other sites
  • 2 weeks later...

To expand on Armit's answer.....

...in SI engines, you can have hot-spots where carbon deposits within the cylinder glow causing ignition points in the compression stroke (at the wrong time), valve wear and tear, valve clearances, incorrect spark-plug gap, blocked air filter, no air filter, incorrect valve timing (changing the volumetric efficiency), incorrect retardation during acceleration, incorrect valve timing, worn points/condenser, worn distributor advance mechanism, incorrectly tuned inlet ports, fuel emulsification of the inlet ports, insufficient atomisation of fuel, blocked exhaust, missing exhaust, Incorrect RON ("OCTANE RATING") of fuel, blocked carburetor jets/injectors....I'm sure there are likely to be a few more....

...I'm a little out of practice with Diesel (CI) troubleshooting though.

Link to post
Share on other sites
  • 2 months later...
  • 1 year later...
  • 2 years later...
In a gasoline engine a "cylinder missfire" would be when the air and gasoline mixture in one or more cylinders does not ignite. 
Three general causes might be found.
1.) Ignition system defects (spark plug, plug wire, coil, etc)
2.) Fuel system problems (injector, improper fuel/air mixture ratio)
3.) Compression parts worn or damaged (piston, rings, valves, head gasket, etc.)
Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Join Mechanical Engineering network

    Join us (login) to get full access : Please sign up to connect and participate.

    To download files...please login

  • Create New...