Cuts Out, Misses. Oldsmobile Shelby Series 1 1999

For 1990-2009 cars only

Makes 🢒 Oldsmobile 🢒 1999 🢒 Shelby Series 1 🢒 Engine 🢒 Engine Controls - 4.0L 🢒 Cuts Out, Misses

Checks

Action

DEFINITION: A steady pulsation or jerking that follows engine speed, which is usually more pronounced as the engine load increases. This condition is not normally felt above 1,500 RPM or 48 km/h (30 mph). The exhaust has a steady spitting sound at idle or at low speed.

Preliminary

•	Refer to Important Preliminary Inspections Before Starting in Symptoms .

•	Search for bulletins.

•	Inspect the PCM grounds for being clean, tight, and in the proper locations. Refer to Engine Controls Schematics .

•	Remove the air filter element and inspect for dirt or for being restricted. Refer to Air Filter Element Service . Replace if necessary.

Fuel System

•	Test the fuel injectors. Refer to Fuel Injector Solenoid Coil Test - Engine Coolant Temperature Between 10-35 Degrees C (50-95 Degrees F) .

•	Test for proper fuel pressure. Refer to Fuel System Diagnosis .

•	Test for a restricted fuel filter. Refer to Fuel System Diagnosis .

•	Inspect for a contaminated fuel condition. Refer to Alcohol/Contaminants-in-Fuel Diagnosis .

•	Inspect the items which can cause an engine to run rich. For a rich condition, refer to DTC P0132 HO2S Circuit High Voltage Bank 1 Sensor 1 and DTC P0152 HO2S Circuit High Voltage Bank 2 Sensor 1 .

•	Inspect items that can cause an engine to run lean. For a lean condition, refer to DTC P0131 HO2S Circuit Low Voltage Bank 1 Sensor 1 and DTC P0151 HO2S Circuit Low Voltage Bank 2 Sensor 1 .

Sensor/System

Use a scan tool in order to monitor the knock sensor (KS) system for excessive spark retard activity. Refer to Knock Sensor (KS) System Description .

Ignition System

•	Wet down the secondary ignition system with water from a spray bottle. Wetting down the secondary ignition system may help locate damaged or deteriorated components. Look and listen for arcing or misfiring as you apply water.

•	Test for proper ignition voltage output with the J 26792 spark tester.

•	Remove the spark plugs and inspect for the following conditions:

-	Correct heat range

Wet plugs

Cracks

Wear

-	Improper gap

-	Burned electrodes

-	Heavy deposits

•	An improper spark plug gap will cause a driveability concern. Gap the spark plugs using a wire gauge gap tool.

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Determine the cause of the fouling before replacing the spark plugs if the spark plugs are gas, coolant or oil fouled. Refer to DTC P0172 Fuel Trim System Rich Bank 1 or DTC P0175 Fuel Trim System Rich Bank 2 for diagnosis of the rich condition. Refer to Spark Plug Visual Diagnosis for diagnosis of coolant or oil fouled spark plugs.

•	Visually and physically inspect the secondary ignition for the following:

-	Ignition wires arcing to ground

-	Ignition wires for proper routing

-	Ignition coils for cracks or carbon tracking

Engine Mechanical

•	Inspect engine mechanical for the following:

-	Test compression

-	Sticking or leaking valves

-	Worn camshaft lobes

-	Valve timing

-	Bent push rods

-	Worn rocker arms

-	Broken valve springs

-	Excessive oil in combustion chamber-Leaking valve seals

•	For incorrect basic engine parts, inspect the following components:

Camshaft

-	Cylinder heads

-	Pistons, etc.

Additional Checks

•	Inspect the following exhaust system components for possible restrictions:

-	The exhaust system for physical damage

-	The exhaust manifold for a collapsed inner wall

-	The mufflers for heat distress or possible internal failure

-	The three-way catalytic converters (TWC) for possible plugged pipes by comparing the exhaust system back pressure on each side of engine

•	Electromagnetic interference (EMI) on the reference circuit can cause an engine miss condition. A sudden increase in RPM with little change in actual engine RPM change indicates that EMI is present. Inspect for high voltage components near the ignition control circuits if a condition exists.

•	Inspect the intake manifold and the exhaust manifold passages for casting flash.