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 ^ Check for alcohol or water in fuel. Perform ALCOHOL IN FUEL TEST. See ALCOHOL IN FUEL TEST.
^ Drain fuel tank and add clean fuel. See FUEL TANK DRAINING.



Restricted fuel filter/line ^ Replace filter/repair restricted line.



Low fuel pressure ^ Check fuel pressure. See FUEL SYSTEM PRESSURE TEST.



Fuel Metering ^ Plugged fuel injectors.
^ Perform injector service (cleaning).