what is the effect on an engine when running lean.....or rich....i did a search but did not come up with anything that was useful....thanks in advance

 

Rich just surpressed power and fouls spark plugs.
Lean can lead to increase combustion temperatures with uncontrolled air/fuel mixtures combustion - this is called detonation.&nbsp Severe detonation can cause damage to engine components and eventually kill the motor.




-Ted