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, refer to FUEL SYSTEM DIAGNOSIS

Faulty fuel pressure regulator - Check fuel pressure, refer to FUEL SYSTEM DIAGNOSIS

Contaminated fuel - Check for water or excessive alcohol in fuel
- Drain fuel tank and add clean fuel

Dirty fuel filter - Replace fuel filter

Lean operating condition - Check computer controls, refer to COMPUTERIZED ENGINE CONTROLS

Vacuum leak - Inspect vacuum hoses for proper routing and damaged lines
- Check intake manifold and throttle body base