Lack of Power

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

PRELIMINARY CHECKS
^ Perform the careful visual/physical checks as described in "PRELIMINARY CHECKS". Preliminary Checks
^ Compare customer's vehicle to similar unit. Make sure the customer has an actual problem.
^ Remove air filter and check air filter for dirt, or for being plugged. Replace as necessary.

IGNITION SYSTEM
^ Check Ignition timing, using "Scan Tool"
^ Check secondary voltage using a spark tester J-26792 (ST-125) or equivalent to check for a weak coil.

ENGINE MECHANICAL
^ Check engine valve timing and compression.
^ Check engine for correct or worn camshaft.

FUEL SYSTEM
^ Check for restricted fuel filter.
^ Check fuel pressure. Refer to "DIAGNOSTIC CHARTS / A-CHARTS / CHART A-7 FUEL SYSTEM DIAGNOSIS". A - Charts
^ Check for contaminated fuel.
^ Check Fuel Injectors are correct for vehicle.

ADDITIONAL CHECKS
^ Check ECM grounds for being clean, tight and in their proper locations. See ECM wiring diagrams.
^ Check alternator output voltage. Repair if less than 9 or more than 16 volts.
^ Check: Exhaust system for possible restriction. Refer to "DIAGNOSTIC CHARTS / A-CHARTS / CHART B-1 B - Charts.
- Inspect exhaust system for damaged or collapsed pipes.
- Inspect muffler for heat damage or possible internal failure.
- For possible plugged three way catalytic converter by comparing exhaust system back pressure on each side at engine.

^ Check: Torque converter clutch for proper operation.