For 1990-2009 cars

## Lack of Power, Sluggishness, or Sponginess Petrol

Checks | Action
--- | ---
DEFINITION: The engine delivers less than expected power. There is little or no increase in speed when partially applying the accelerator pedal.
Preliminary Checks |

• | Refer to Important Preliminary Checks in Symptoms - Engine Controls .

| Important:: Do not compare the power output of the vehicle while operating on LPG to a vehicle operating on petrol. Both fuels have different drive feel characteristics.

• | Verify the customers concern by comparing the power output of a similarly equipped known good vehicle to the suspect vehicle.

• | Inspect the air filter for correct type and for dirt or restriction.

• | Test the transmission for correct shift pattern and downshift operation.

• | Inspect the LPG ECM for the correct LPG calibration. Program the LPG ECM if necessary.

Fuel System Checks |

• | Test for correct fuel system pressures. Refer to Fuel System Diagnosis .

• | Inspect the lock-off filter and LPG fuel filter for restriction. Refer to Fuel Filter Replacement .

Ignition System Checks |

| Important:: A higher secondary ignition voltage is required to operate the vehicle on LPG than on petrol.

• | Test for correct secondary ignition system voltage output using only the combustible gas detector Spark Tester.

| Important:: More timing advance is required to operate the vehicle on LPG than on petrol.

• | Test for correct operation of the Knock Sensor system.

Exhaust System Checks | Inspect the exhaust system for a possible restriction. Restrictions can include the following:

• | A failed catalytic converter

• | Damaged or collapsed pipes

• | An internally failed muffler - may show signs of heat distress

Engine Mechanical Checks | Test for correct engine operation by checking for the following:

• | Correct engine compression

• | Correct engine valve timing

• | Worn or incorrect camshafts

Additional Checks |

• | Test for correct A/C operation. A/C that is on all the time may cause this symptom.

• | Test for correct transmission torque converter clutch (TCC) operation, if equipped.

• | Test for correct generator operation.

• | Inspect for correct operation of the accelerator pedal. A stretched accelerator cable may cause this symptom.