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Typically when the engine misfires it will feel like jerking. Find out why the engine is misfiring; run a computer diagnostic test and the computer should reveal the answer.
Misfiring on a petrol injection engine is caused due to incorrect ignition timing. As the engine rotates, the timing determines when each piston fires or ignites.
When the engine is cold or when it is misfiring.
Check your engine timing, it may be too slow.
Engine cylinders # 1 and # 4 are misfiring
Timing belt. misfiring engine
The flashing check engine light means there is one or more cylinder misfires occuring.Have the codes pulled from the computer to determine which cylinder(s) are misfiring.
The number 5 engine cylinder is misfiring
by sensing engine RPM it can teel if engine is not running smooth by sensing the rotation of the rpm's of the engine.
The catalytic converter