Cuts Out, Misses. GMC Truck Safari

For 1990-2009 cars only

Makes 🢒 GMC_Truck 🢒 2002 🢒 Safari - 4WD 🢒 Engine 🢒 Engine Electrical 🢒 Cuts Out, Misses

Inspections

Action

DEFINITION: A jerking that follows engine speed, usually more pronounced as the engine load increases which is not normally felt above 1,500 RPM or 48 km/h (30 mph).

Preliminary

Refer to Symptoms - Engine Controls .

Ignition System

•	Inspect for a cylinder misfire:

1.	Start the engine.

2.	Allow the engine to stabilize.

3.	Disconnect the idle air control (IAC) motor.

•	Inspect the spark plugs. Refer to Spark Plug Inspection .

•	Inspect the spark plug wire resistance. Refer to Ignition System Specifications .

•	Inspect the distributor. Refer to Distributor Inspection .

•	Perform the Fuel Injector Balance Test. Refer to Fuel Injector Balance Test with Tech 2 .

Engine Mechanical

•	Perform a cylinder compression check. Refer to Engine Compression Test in Engine Mechanical.

•	Inspect the engine for the following:

-	Improper valve timing

-	Bent pushrods--Refer to Valve Rocker Arm and Push Rod Cleaning and Inspection in Unit Repair.

-	Worn rocker arms--Refer to Valve Rocker Arm and Push Rod Cleaning and Inspection in Unit Repair.

-	Worn camshaft lobes--Refer to Alcohol/Contaminants-in-Fuel Diagnosis in Unit Repair.

-	Broken or weak valve springs -- Refer to Upper Engine Noise, Regardless of Engine Speed in Engine Mechanical.

•	Inspect the intake and exhaust manifold passages for casting flash. Refer to Intake Manifold Cleaning and Inspection in Unit Repair.

Fuel System

•	Test the fuel pressure. Refer to Fuel System Diagnosis .

•	Inspect for water contamination in the fuel. Refer to Alcohol/Contaminants-in-Fuel Diagnosis .

•	Perform the fuel injector coil test. Refer to Fuel Injector Solenoid Coil Test .

•	Perform the fuel injector balance test. Refer to Fuel Injector Balance Test with Tech 2 .