Hesitation, Sag, Stumble. Cadillac Eldorado 2000

For 1990-2009 cars only

Makes 🢒 Cadillac 🢒 2000 🢒 Eldorado 🢒 Engine 🢒 Engine Controls - 4.6L 🢒 Hesitation, Sag, Stumble

Checks

Action

DEFINITION: Momentary lack of response as the accelerator is pushed down. Can occur at any vehicle speed. Usually more pronounced when first trying to make the vehicle move, as from a stop sign. May cause the engine to stall if severe enough.

Preliminary

•	Refer to Important Preliminary Check Before Starting in Symptoms .

•	Search for bulletins.

Sensor/System

•

Check the HO2S for proper operation. The sensors should respond quickly to different throttle positions. If not, check the sensors for silicon from RTV sealant, or other contaminants from the fuel. The sensors may have a white powdery coating. Silicon contamination causes a false high signal voltage (rich exhaust indicated). The PCM will reduce the amount of fuel delivered to the engine.

•	Check the MAP sensor for proper operation.

•	Check the throttle body, TP sensor, and accelerator cables for proper operation.

•	Check the EGR System for proper operation.

Fuel System

•	Check the fuel pressure. Refer to Fuel System Pressure Test .

•	Check the fuel injectors. Refer to:

-	Fuel Injector Balance Test with Special Tool

-	Fuel Injector Balance Test with Tech 2

-	Fuel Injector Solenoid Coil Test - Engine Coolant Temperature Between 10-35 Degrees C (50-95 Degrees F)

-	Fuel Injector Solenoid Coil Test - Engine Coolant Temperature Outside 10-35 Degrees C (50-95 Degrees F)

•	Check for items that cause the engine to run rich, or lean.

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

Ignition System

•	Check the IC circuits for proper connections at each ignition module assembly.

•	Check for proper ignition voltage output using the J 26792 spark tester.

•	Check the ignition coils for cracks, or damage.

•	Check for a missing or damage ignition module assembly grounding spring.

•	Check for misaligned or damaged spark plug boots.

Important: If the spark plugs are gas or oil fouled, the cause of the fouling must be determined before replacing the spark plugs.

•	Check the spark plugs for the following conditions:

Fouling

Cracks

Wear

-	Improper gap

-	Improper heat range and/or reach

-	Burned or damaged electrodes.

Automatic Transaxle

Check for proper operation of the transmission fluid pressure (TFP) manual valve switch. Refer to Transmission Fluid Pressure Manual Valve Position Switch Circuit Diagnosis in Automatic Transaxle 4T80-E.

Additional Checks

Visually/physically inspect the vacuum hoses for splits, kinks, damage, or improper connections or routing. Refer to the Vehicle Emission Control Information label.