Lack of Power/Sluggish/Spongy/Stumble

DESCRIPTION
Engine delivers less than expected power. Little or no increase in speed when accelerator pedal is pushed down part way. Perform careful visual check as described in When To Use This Section. Compare customer's car to similar unit. Make sure the customer's car has an actual problem. - When to Use This Section

INSPECTION
^ Remove air filter and check for dirt or for being plugged. Replace as necessary.

^ Restricted fuel filter, contaminated fuel or improper fuel pressure. Refer to Diagnostic Charts / A-Charts / Chart A-7. Chart A-7 Fuel System Diagnosis

^ Electronic Control Module (ECM) power grounds, see Computers and Controls / Diagrams. Diagrams

^ Exhaust Gas Recirculation (EGR)Valve operation for being open or partly open all the time. Refer to C-charts Component Testing / Chart C-7. Chart C-7 Exhaust Gas Recirculation (EGR) Check

^ Exhaust System for possible restriction. Refer to Diagnostic Charts / B-Charts. B Charts

^ Inspect exhaust system for damaged or collapsed pipes.

^ Inspect muffler for heat distress or possible internal failure.

^ Generator output voltage. Repair if less than 9 or more than 16 volts.

^ Engine valve timing and compression.

^ Engine for proper or worn camshaft.

^ Secondary voltage using a shop oscilloscope or a spark tester J 26792 (ST-125) or equivalent.

^ Check A/C operation. A/C clutch should cut out at wide open throttle. Refer to C-charts Component Testing / Chart C-10A. Chart C-10A A/C Clutch Control