Misses Under Load
Definition: 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
Contaminated fuel Drain fuel tank and add clean fuel
Restricted fuel filter/line Replace filter/repair restricted line
Low fuel pressure Test fuel pressure
Proceed to FUEL PRESSURE TEST
Fuel Injected Plugged fuel injectors
Perform injector balance test
Perform injector service (cleaning)
Proceed to MAINTENANCE PROCEDURES