NGK 90156 Spark Plug

NGK Laser Iridium Spark Plug 90156

NGK 90156 is a Laser Iridium spark plug built for OE-style ignition performance in select Cadillac CTS, Chevrolet Camaro, Chevrolet Corvette, and Ford Mustang applications. It uses an iridium center electrode, nickel ground electrode, and a tapered seat to support consistent combustion and reliable spark delivery.

The Laser Iridium Spark Plug line combines NGK’s OE-focused engineering with durable electrode materials and precise gap control. For drivers servicing a 2013-2015 Cadillac CTS, 2012-2015 Chevrolet Camaro, 2006-2011 Chevrolet Corvette, or 2013-2014 Ford Mustang, part number 90156 is a direct-fit ignition service option.

Key Features

• Part number 90156 / NGK ITR6G9
• Laser Iridium center electrode tip for stable spark performance
• Nickel ground electrode with standard configuration
• Pre-gapped at .036 in. with 5,000 ohms resistance
• Copper core center electrode for efficient heat transfer
• Tapered seat, 14 mm thread diameter, 5/8 in. hex
• OE-equivalent design for listed Cadillac, Chevrolet, and Ford applications

Product Details

NGK manufactures this spark plug with an iridium firing tip and a copper-core center electrode to support dependable ignition under everyday driving and higher-load conditions. The 6 heat range, .708 in. reach, and non-removable nut terminal match the listed OE-style specifications for the covered vehicles. This part cross-references DENSO Auto Parts 4512 for the same application.

What It Helps Address

• Rough idle caused by worn spark plugs
• Hard starting from weakened ignition output
• Misfire codes related to plug wear or gap growth
• Reduced throttle response from inconsistent spark delivery
• Service intervals on high-output Cadillac CTS, Chevrolet Camaro, Chevrolet Corvette, and Ford Mustang engines

Installation Notes

• Verify engine application and cylinder count before installation.
• Check the specified gap for your vehicle; listed fitments include .040 in. and .036 in. OE-equivalent requirements.
• Use the correct torque procedure for tapered-seat spark plugs.
• Inspect ignition coils, boots, and plug wells during service.
• Confirm the part number 90156 matches the engine specification before final assembly.

Quality Assurance

NGK is a long-established OE supplier and manufacturer with broad coverage across domestic and import vehicles. Part number 90156 reflects NGK’s OE-focused manufacturing standards for durability and consistent ignition performance in the listed applications.

Compatible Vehicles

• Fits 2013-2015 Cadillac CTS, N/A
• Fits 2012 Cadillac CTS, N/A
• Fits 2009-2011 Cadillac CTS, N/A
• Fits 2014-2015 Chevrolet Camaro, N/A
• Fits 2012-2015 Chevrolet Camaro, N/A
• Fits 2012-2013 Chevrolet Corvette, N/A
• Fits 2006-2011 Chevrolet Corvette, N/A
• Fits 2013-2014 Ford Mustang, N/A