Engine Misses Under Load

SYMPTOM DESCRIPTION:

Steady pulsation or jerking that follows engine speed, usually more pronounced as engine load increases. The exhaust has a steady spitting sound at idle or low speed.




POSSIBLE CAUSE ACTION

Improper fuel - Drain fuel tank, flush system,
and fill with proper fuel. Change
fuel filter.




Empty fuel tank or - Fill tank.
fuel tank vent blocked - Bleed fuel system.


- Check tank vent.






Air in fuel system - Bleed fuel system.






Clogged fuel filter - Replace fuel filter.





Restricted, blocked, damaged - Remove restriction or
or leaking fuel injector lines replace lines as necessary.
Bleed fuel system.







Leaking or damaged fuel - Replace leaking or damaged
supply lines, or loose lines or tighten connections as
fuel connections needed. Bleed fuel system.






Incorrect injection pump to - Adjust injection pump timing.
engine timing





Damaged or restricted injector - Clean or replace injector
nozzle nozzles.





Malfunctioning injection pump - If injection pump is malfunctioning
or will not adjust properly, replace as
a unit.