Lack of Power/Sluggish/Spongy

Symptom: 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 Generator output voltage.

IGNITION SYSTEM MALFUNCTION - Scope check Ignition System. Check SECONDARY CIRCUIT firing Kv and spark duration.
SEE IGNITION SYSTEM/OSCILLOSCOPE PATTERNS.

- Remove spark plugs and inspect for: cracks, excessive wear, improper gap, burned electrodes, and wet or heavy deposits. Replace as necessary.


- Inspect distributor cap, rotor and spark plug wires for proper plug wire routing, crossfire between spark plugs (in cap) or wires, wires shorting to ground and rotor shorting to ground via distributor shaft.

- Check IGNITION TIMING for excessive spark retard.
SEE IGNITION SYSTEM/ TIMING SPECIFICATIONS

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 valve timing, (timing belt alignment).

EMISSIONS COMPONENT MALFUNCTION - Check EGR valve for binding or sticking in the open position.

- Check EGR Transducer for proper operation.

- Check for plugged or contaminated Catalytic Converter.

FUEL SYSTEM MALFUNCTION - Check plugged or restricted Air Filter.

- Check fuel pressure.

- Check for lean Air-Fuel mixture, (O2S Sensor output).

- Perform injector balance test.

- Check fuel quality.

- Check Throttle Position Sensor for proper operation.

TRANSMISSION MALFUNCTION - Check for proper transmission shift points.

- Check for proper Torque Converter Clutch (TCC) operation.