ACDelco 41-990 Spark Plug

Description:

Features and Benefits:

• ACDelco GM Original Equipment parts are designed, engineered and tested to rigorous standards, and are backed by General Motors
• Approved by US Legal 7/31/19
• Double platinum point pad on center and ground electrode offer excellent durability and consistent voltage demands to help reduce wear on ignition system
• GM Engineers design and validate OE parts specifically for your Chevrolet, Buick, GMC, or Cadillac vehicle
• GM regularly updates production and service part designs to integrate new materials and technologies
• One-piece, fired-in suppressor seal blends three glass types for a gas-tight seal that helps reduce radio frequency and engine interference, regulate spark plug energy, and protect against compression pressures for long life
• Some ACDelco GM Original Equipment parts may have formerly appeared as GM Genuine Parts (OE) or ACDelco Professional

Specifications:

Features and Benefits:

• – Apply dielectric grease into the boot area to reduce the chance of exterior tracking on the buttress tower of the spark plug. This grease also promotes a good heat transfer between the spark terminal screw and boot terminal.
• – Before installing new spark plugs, use a gap guide to make sure your new spark plugs have the correct gap. NOTE: ACDelco GM OE Iridium Spark Plugs are pre-gapped during manufacturing. Never attempt to gap an ACDelco GM OE Iridium Spark Plug. You could damage the spark plug. Replace any incorrectly gapped ACDelco GM OE Iridium Spark Plugs with plugs that are correctly gapped.
• – Brush or air blast dirt away from the well areas before removing spark plugs. CAUTION: Use goggles to protect eyes from debris when applying compressed air to spark plug wells.
• – Grasp the spark plug boot and gently rotate it 90 degrees counterclockwise. Pull the spark plug boot and cable away from the spark plug. If necessary, use a spark plug boot removing tool. DO NOT grab or violently pull spark plug cables
• – Install spark plugs or glow plugs to the proper torque per the manufacturers' specification.
• – Remove each spark plug and place each one in a tray by cylinder number. This will help identify and relate any unusual condition to the cylinder involved.
• – Use the correct deep socket size to loosen each spark plug one or two turns. NOTE: To remove spark plugs from aluminum heads, allow the engine to cool. The heat of the engine, in combination with a spark plug that is still hot, may cause the spark plug threads to strip the cylinder head upon removal.
• Visually inspect spark plugs for signs of wear. Follow these steps for removing spark plugs for inspection, servicing or replacement:

Specifications: