Lack of Power, Sluggishness, or Sponginess. Cadillac Eldorado 1999

For 1990-2009 cars only

Makes 🢒 Cadillac 🢒 1999 🢒 Eldorado 🢒 Engine 🢒 Engine Controls - 4.0L and 4.6L 🢒 Lack of Power, Sluggishness, or Sponginess

Checks

Action

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

Preliminary Checks

•	Refer to Symptoms, Important Preliminary Checks Before Starting.

•	Search for bulletins.

•	Check PCM grounds for being clean, tight and in their proper locations.

•	Remove and check air filter element for dirt, or for being restricted. Replace as necessary.

Fuel System Checks

•	Check for low fuel pressure. Refer to Fuel System Pressure Check.

•	Check for restricted fuel filter.

•	Check for contaminated fuel. Refer to Fuel Quality Diagnosis.

•	Check items which can cause an engine to run rich (long term fuel trim near -99%).

•	Check items that can cause an engine to run lean (long term fuel trim near 100%).

Sensor/System Checks

•	Using a scan tool, monitor KS system for excessive spark retard activity.

•	Check the EGR system for proper operation.

Ignition System

•	Wetting down the secondary ignition system with water from a spray bottle may help locate damaged or deteriorated components. Look/listen for arcing or misfiring as water is applied.

•	Check for proper ignition voltage output with spark tester J 26792. Refer to Secondary Ignition System Diagnosis.

•	Remove spark plugs and check for the following:

Wet plugs

Cracks

Wear

-	Improper gap

-	Burned electrodes

-	Heavy deposits

•	An improper spark plug gap will cause a driveability problem. The spark plug gapping should be done using a wire gauge gap tool (J 41319). If spark plugs are gas or oil fouled, the cause of the fouling must be determined before replacing the spark plugs.

•	Check for loose ignition control module ground.

•	Spark plugs for proper heat range. Refer to Owners Manual or General Information.

Engine Mechanical

•	Excessive oil in combustion chamber-Leaking valve seals. Refer to Engine Mechanical.

•	Low cylinder compression. Refer to Engine Mechanical.

•	For incorrect basic engine parts. Inspect the following:

Camshaft

-	Cylinder heads

-	Pistons, etc.

Refer to Engine Mechanical.

Additional Checks

•	Check exhaust system for possible restrictions. Check for the following:

-	Inspect exhaust system for damaged or collapsed pipes.

-	Inspect mufflers for heat distress or possible internal failure.

-	For possible plugged Three-Way catalytic converters by comparing exhaust system back pressure on each side of engine. Refer to Restricted Exhaust System Check and Exhaust System.

•	Check Torque Converter Clutch (TCC) for proper operation. Refer to Automatic Transaxle.

•	Traction Control system brake switch assembly. Loss of performance can result from an improperly adjusted or a failed extended travel brake switch. The PCM operates in the Torque Management mode when the PCM detects the brake pedal and throttle are depressed at the same time.