Surges at Steady Speed

Definition: 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 capacity Check fuel capacity.

Faulty fuel pressure regulator Check fuel pressure.

Contaminated fuel Check for water or
excessive alcohol in fuel. Alcohol In Fuel Test
Drain fuel tank and add clean fuel

Dirty fuel filter Replace fuel filter.

Lean operating condition Check computer controls.

Vacuum leak Inspect vacuum hoses for
proper routing and damaged lines
Check intake manifold and throttle chamber