GM Genuine Parts 68G Glow Plug (12690238) for Diesel Engines | Cold Start Heat

GM Genuine Parts 68G Glow Plug (12690238) is designed to deliver targeted heat when diesel engines need it most during cold starts. It uses a GN type regulating coil and a self regulating design to manage electrical flow as temperatures rise, helping to prevent overheating and reduce wear on electrical systems.

This OE grade part is engineered, tested, and backed by General Motors, with compatibility considerations across Chevrolet, Buick, GMC and Cadillac vehicles. Some GM Genuine Parts may have formerly appeared as ACDelco GM Original Equipment OE, reflecting a history of GM engineering excellence and ongoing innovation to meet modern materials and technologies.

How it works

The GN type regulating coil maintains steady heat output for reliable cold starts. The self regulating feature adjusts current draw as the engine warms, supporting stable operation and potentially lowering battery strain in challenging conditions.

Designed for robust performance, this glow plug is built to suit a wide range of chamber requirements, ensuring the right fit for many GM engines while respecting OE design intent.

Key features

• Heat rich design aimed at diesel cold starts
• GN type regulating coil for consistent heat output
• Self regulating to control electrical flow as temperatures rise
• Full reach range from 21 mm to 40 mm to fit multiple chamber sizes
• OE grade reliability backed by GM
• GM engineers design and validate OE parts for Chevrolet, Buick, GMC and Cadillac
• Regular design updates incorporate new materials and technologies

Compatibility and quality

GM Genuine Parts are designed, engineered and tested to rigorous standards and are backed by General Motors. This 68G glow plug supports OEM fit and function, helping you maintain authentic GM performance for diesel cold starts and consistent operation across seasons.

Real world use and benefits

In cold climates or with engines that sit idle for periods, rapid heating of the combustion chamber can improve starting reliability. The 68G glow plug may help support quicker warm ups, smoother engine start sequences, and steady electrical behavior under varying temperatures, all while aligning with GM’s OE design philosophy.

Why choose GM Genuine Parts

• OE fit and function for GM vehicles
• Rigorous engineering and testing backed by GM
• Ongoing updates to materials and production designs

When selecting parts for your Chevrolet, Buick, GMC or Cadillac, GM Genuine Parts offer an authentic option built to the brand’s standards. Always verify compatibility with your specific engine model and follow service manual guidance for replacement and installation.