Surges at Steady Speed

SYMPTOM DESCRIPTION:

Engine power variation under steady throttle or cruise. Feels like the car speeds up and slows down with no change in accelerator pedal.


POSSIBLE CAUSE ACTION

Insufficient fuel flow ^ Check fuel pump volume


Faulty fuel pressure regulator ^ Check fuel pressure.


Contaminated fuel ^ Check for water or excessive alcohol in fuel.


Restricted fuel filter ^ Replace fuel filter, refer to "Component Replacement and Repair Procedures"


Lean air/fuel mixture ^ Check computer controls, refer to "Computers And Control Systems"


Plugged fuel injector ^ Perform injector balance test.


Vacuum leak ^ Inspect vacuum hoses for proper routing and damaged lines.

^ Check intake manifold/throttle body area.