Lack of Power, Sluggish or Spongy

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. Testing and Inspection
^ Compare customers vehicle with a similar unit. Make sure the customer has an actual problem.
^ Remove air filter
^ Check for dirt, or for air ducts being plugged clean or, replace as necessary.
^ Check the transmission shift pattern and down shift operation.
^ Check fuel quality, refer to Fuel System. Testing and Inspection
^ Check engine oil level and quality.

FUEL SYSTEM CHECKS

^ Check the fuel supply to injection pump and fuel return from injection pump. Refer to Fuel Supply System Checks.
^ Check fuel pump operation. Refer to Fuel Supply System Checks. Component Tests and General Diagnostics
^ Check for faulty fuel injection nozzles. Refer to Injection Nozzles. Testing and Inspection

EXHAUST SYSTEM CHECKS

^ Check the exhaust system for a possible restriction. Refer to Exhaust Systems.
^ Inspect the exhaust system for damaged or collapsed pipes.

AIR INTAKE SYSTEM CHECKS

^ Check for an air leakage or restriction in air inlet ducks or intake manifold.
^ Check for a worn or damaged turbo charger turbine wheel, shaft or compressor wheel.

ENGINE MECHANICAL CHECK
Check the engine for the following:

^ Low compression
^ Improper valve timing
^ Improper or worn camshaft additional Checks
^ Check the control module grounds for being clean, tight, and in their proper location. Refer to Component Locations.
^ Check the Torque Converter Clutch (TCC) operation.
^ Check the A/C operation. Refer to A/C Systems. Testing and Inspection
^ Check the generator output voltage. Repair if less than 9 or more than 16 volts.