Curiosii for ever!: Car repair manuals for everyone.

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 customers car to similar unit. Make sure the Vehicle has an actual problem.
- Remove Air Filter and check Air Filter for dirt, or for being plugged. Replace as necessary.

FUEL SYSTEM
CHECK: Restricted Fuel Filter.
CHECK: Fuel Pressure, Refer to Diagnostic Charts / Chart A-7.
A-7: Fuel System Diagnosis

CHECK: Contaminated Fuel.
CHECK: Fuel Injectors are correct for the Vehicle.

IGNITION SYSTEM
CHECK: Ignition timing, using "Scan Tool".
CHECK: Secondary voltage using an Oscilloscope or a Spark Tester J-26792 (ST-125), or equivalent, to check for a weak coil.

ADDITIONAL CHECKS
CHECK: Engine Control Module grounds for being clean, tight and in their proper locations.
CHECK: Exhaust Gas Recirculation operation for being open or partly open all the time. Refer to Diagnostic Charts / Chart C-7.
Chart C-7A: EGR System Check

CHECK: Generator output voltage. Repair if less than 9 or more than 16 volts.
CHECK: Exhaust System for possible restriction. Refer to Diagnostic 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 three way Catalytic Converter Clutch for proper operation.

ENGINE MECHANICAL
CHECK: Engine Valve timing and compression.
CHECK: Engine for correct or worn Camshaft.