ACDelco GM Original Equipment LS Iridium Spark Plug 

Denso Iridium #20 Also used in TA2 engines

Product Specifications

Master Your Engine Tune-Up Maintenance Guide

Keep your engine running at peak performance with proper spark plug care. Whether you are experiencing engine hesitation, poor acceleration, or difficulty starting, a fresh set of spark plugs can restore your vehicle's power and fuel efficiency.

Follow these professional maintenance practices to ensure a safe and effective installation.

Step 1: Safe Removal & Preparation

Before beginning, ensure your workspace is clean and that you have the right tools for the job.

• Handle with Care: Grasp the spark plug boot and gently rotate it 90° counterclockwise. Pull the boot and cable away from the plug.

  Pro Tip: If the boot is stubborn, use a dedicated removal tool. Never grab or violently pull the spark plug cables, as this can damage the internal wiring.

• Clear the Debris: Use a brush or compressed air to blast dirt away from the spark plug well areas before removal.

  Safety First: Always wear protective goggles when using compressed air to prevent eye injury from flying debris.

• Cool Down for Aluminum Heads: If your engine has aluminum cylinder heads, allow it to cool completely before removal. Removing a hot plug from a hot aluminum head can lead to stripped threads.

Step 2: Inspection & Diagnosis

Organizing your old plugs can tell you a lot about your engine's health.

• Track Your Plugs: Place each removed spark plug in a tray labeled by cylinder number. This helps you identify if a specific cylinder is running lean, rich, or oil-fouled.

• Signs of Failure: Inspect for technical defects such as:

  • Cracks in the upper or lower insulator.

  • Chipped or broken insulator tips.

  • Damaged or brittle spark plug boots.

Step 3: Precision Installation

The difference between a perfect tune-up and an engine misfire often comes down to the details.

• The Dielectric Advantage: Apply dielectric grease to the inside of the boot area. This reduces the risk of "tracking" (electrical arcing) and promotes efficient heat transfer between the terminal screw and the boot.

• Check the Gap: Use a precision gap guide to verify the clearance before installation.

  • CRITICAL NOTE: ACDelco GM OE Iridium Spark Plugs are pre-gapped at the factory. Never attempt to gap an Iridium plug, as you may damage the delicate electrode. If the gap is incorrect, replace the plug entirely.

• Torque to Spec: Hand-tighten the plugs first to avoid cross-threading, then use a torque wrench to tighten to the manufacturer's specific torque rating.

Technical Specifications Summary

FITMENT | 2012-2015 Camaro- 2006-2013 Corvette - 2009-2015 Cadillac CTS

 WARNING: Cancer and Reproductive Harm -- www.P65Warnings.ca.gov