Lack of Power/Sluggish/Spongy

SYMPTOM DESCRIPTION:


Engine delivers less than expected power. Little or no increase in speed when accelerator is pushed down part way.


POSSIBLE CAUSE ACTION


Charging System Malfunction Check Battery voltage.

Check Alternator output voltage.




Ignition System Malfunction Scope check Ignition System

Check IGNITION COIL for proper output voltage.

Check SPARK PLUGS for proper spark duration. Remove spark plugs, check for fuel fouled plugs, cracks, wear, improper gap, burned electrodes, or heavy deposits. Replace as necessary.

Check SECONDARY CIRCUIT for abnormal firing Kv, crossfire between spark plugs (distributor cap, spark plug wires), and proper plug wire routing.

Check IGNITION TIMING for excessive spark retard.

Check for incorrect distributor installation.



Engine Mechanical Malfunction Check COMPRESSION Perform a compression check, and cylinder leakage test, look for weak cylinders.

Check for VACUUM LEAKS inspect Intake manifold, gasket(s), and hoses.

Check exhaust system for leaks, restriction, or damage.

Check for incorrect valve timing.



Emissions Component Malfunction Check for plugged or contaminated Catalytic Converter.



Fuel System Malfunction Check for incorrect Air-Fuel mixture, O2 Sensor, perform injector balance test, inspect regulator operation (check vacuum line and return hose), check fuel pressure.

Check for defective Fuel Pump Ballast Bypass Relay.

Check plugged or restricted Fuel Filter.

Check plugged or restricted Air Filter.

Check fuel quality.



Transmission Malfunction Check for proper transmission shift points.

Check for proper Torque Converter Clutch (TCC) operation.