{"product_id":"gm-genuine-parts-glow-plug-68g-12690238-for-chevrolet-buick-gmc-cadillac-gn-type-self-regulating-fast-heat-oem-fit","title":"GM GENUINE PARTS Glow Plug 68G (12690238) for Chevrolet\/Buick\/GMC\/Cadillac — GN-type self-regulating, fast-heat OEM fit","description":"\u003cp\u003e\u003cstrong\u003eGM Genuine Parts 68G (12690238) glow plug is an OEM-quality diesel engine heating element engineered to provide reliable cold-start assistance by delivering controlled heat to the combustion chamber.\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cp\u003eDesigned and validated by GM engineers, this glow plug uses a GN-type self-regulating coil to heat faster at low temperatures and limit current as it warms. It matches original equipment fitment and reach options, so it installs like the part your Chevrolet, Buick, GMC, or Cadillac was built with. The construction and testing standards reflect General Motors' service-part specifications for durability and consistent performance across a wide range of diesel applications.\u003c\/p\u003e\n\n\u003ch3\u003eHow does this glow plug improve cold starts?\u003c\/h3\u003e\n\u003cp\u003eThe GN-type regulating coil heats rapidly to help raise combustion-chamber temperature before fuel injection, which reduces rough cranking and white smoke during initial starts. Its self-regulating behavior prevents excessive current draw as temperature rises, helping preserve battery life and electrical components.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eGN-type coil for fast initial heat\u003c\/li\u003e\n  \u003cli\u003eSelf-regulating to avoid overheating and excess battery drain\u003c\/li\u003e\n  \u003cli\u003eEngineered to meet GM OE electrical and thermal tolerances\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWill this fit my diesel vehicle and how do I choose the right reach?\u003c\/h3\u003e\n\u003cp\u003eGM provides a range of reach lengths—21 mm to 40 mm—so technicians can match the glow plug to the combustion-chamber depth and OEM specification for each engine. Using the correct reach ensures proper heat placement and avoids interference with piston motion or chamber geometry.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eAvailable reaches from 21 mm to 40 mm to match chamber requirements\u003c\/li\u003e\n  \u003cli\u003eDirect-replacement design for compatible Chevrolet, Buick, GMC, and Cadillac diesels\u003c\/li\u003e\n  \u003cli\u003eCheck your vehicle's factory service manual or parts lookup for exact 12690238 fitment\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eHow reliable and durable is the GM Genuine Parts glow plug?\u003c\/h3\u003e\n\u003cp\u003eThese glow plugs are manufactured to GM's production and service standards and undergo validation by GM engineers to ensure consistent operation under typical driving conditions. Materials and coil design are selected to withstand repeated thermal cycles and electrical loads associated with diesel starting routines.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eBuilt and tested to General Motors’ engineering standards\u003c\/li\u003e\n  \u003cli\u003eMaterials and coil design resist thermal fatigue and corrosion\u003c\/li\u003e\n  \u003cli\u003eSome GM Genuine Parts may have formerly appeared as ACDelco GM Original Equipment\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhat should technicians expect during installation and maintenance?\u003c\/h3\u003e\n\u003cp\u003eInstallation follows standard glow-plug replacement procedures: disconnect battery, remove wiring harness, extract the old plug, and torque the new plug to factory specification. Inspect the cylinder head port for carbon buildup and confirm electrical connection integrity to ensure consistent heating performance.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eInstall like an OE replacement—follow factory torque and wiring procedures\u003c\/li\u003e\n  \u003cli\u003eInspect and clean glow-plug bore and connector contacts before assembly\u003c\/li\u003e\n  \u003cli\u003eVerify electrical supply and relay\/function after installation\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eWho is this for: The GM Genuine Parts 68G (12690238) glow plug is intended for owners, fleets, and technicians who require an OEM-spec replacement for diesel engines in Chevrolet, Buick, GMC, or Cadillac models. It’s a practical choice for anyone seeking direct-fit, GM-validated components that match the vehicle’s original design, especially in colder climates or for vehicles showing rough cold starts or reduced preheat performance.\u003c\/p\u003e\n\u003csection class=\"product-faq-snippet\"\u003e\u003ch3\u003eFAQ\u003c\/h3\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: Is the 12690238 glow plug a direct replacement?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: Yes — it’s an OEM-spec direct-fit part for compatible GM diesel engines when matched for the correct reach.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: How do I choose the correct reach length?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: Match the glow plug reach (21–40 mm range) to your engine’s OEM specification found in the service manual or parts lookup.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/section\u003e","brand":"GM GENUINE PARTS","offers":[{"title":"Default Title","offer_id":48083179110558,"sku":"B0842WSRXM","price":54.48,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0781\/2041\/9486\/files\/gm-genuine-parts-glow-plug-front-packaging_jpg.jpg?v=1785827901","url":"https:\/\/northtrailauto.ca\/products\/gm-genuine-parts-glow-plug-68g-12690238-for-chevrolet-buick-gmc-cadillac-gn-type-self-regulating-fast-heat-oem-fit","provider":"North Trail Auto","version":"1.0","type":"link"}