{"product_id":"engine-block-heater-for-jeep-comanche-1987-1992-4-0l","title":"Engine Block Heater for Jeep Comanche (1987-1992) 4.0L","description":"\u003ch2 style=\"font-size: clamp(18px, 3vw, 21px); margin-bottom: 15px; line-height: 1.3;\"\u003eCold-Start Protection Engine Block Heater for 1987-1992 Jeep Comanche (MJ)\u003c\/h2\u003e\n\n\u003cp\u003e\u003cstrong\u003eWhat it Does:\u003c\/strong\u003e The Engine Block Heater pre-warms engine coolant in the cast-iron cylinder block of the 1987-1992 Jeep Comanche to eliminate cold-start wear and deliver immediate cab heat in sub-zero ambient temperatures.\u003c\/p\u003e\n\n\u003ch3\u003eThe Stock Jeep Comanche Cold-Weather Starting Issue\u003c\/h3\u003e\n\u003cp\u003eThe heavy cast-iron block of the \u003cstrong\u003eAMC 242\u003c\/strong\u003e 4.0L engine holds significant thermal mass. In extreme sub-freezing temperatures, high-viscosity motor oil thickens and cannot circulate rapidly across hydrodynamic bearings, piston skirts, and valvetrain components during ignition. This sluggish fluid dynamic causes severe friction wear, excessive starter amp draw, and extreme battery drain during cranking in unheated environments.\u003c\/p\u003e\n\n\u003ch3\u003eThe Engineering Solution\u003c\/h3\u003e\n\u003cp\u003eFeaturing a 600-watt, 120-volt immersion heating element, this heavy-duty core plug unit directly heats the internal coolant jacket. Sized at an exact 2-inch diameter to replace a factory freeze plug in the \u003cstrong\u003eMJ\u003c\/strong\u003e Comanche block, it establishes thermal convection currents that warm both the cylinder walls and internal oil galleries. Engineered by Zerostart under part number \u003cstrong\u003e3100072\u003c\/strong\u003e, it reduces cold-crank friction, speeds up closed-loop ECU fuel management, and prevents premature mechanical fatigue.\u003c\/p\u003e\n\n\u003ch3\u003eTechnical Specifications\u003c\/h3\u003e\n\u003cdiv style=\"overflow-x: auto; margin-bottom: 20px;\"\u003e\n  \u003ctable width=\"100%\" style=\"border-collapse: collapse; border: 1px solid #e0e0e0; font-size: 14px; min-width: 300px;\"\u003e\n    \u003ctr style=\"background-color: #f9f9f9;\"\u003e\n\u003cth style=\"padding:10px; text-align: left; border: 1px solid #e0e0e0;\"\u003eFitment\u003c\/th\u003e\n\u003ctd style=\"padding:10px; border: 1px solid #e0e0e0;\"\u003e1987-1992 Jeep Comanche\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth style=\"padding:10px; text-align: left; border: 1px solid #e0e0e0;\"\u003eEngine \/ Chassis\u003c\/th\u003e\n\u003ctd style=\"padding:10px; border: 1px solid #e0e0e0;\"\u003eAMC 242 4.0L I6 \/ MJ\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr style=\"background-color: #f9f9f9;\"\u003e\n\u003cth style=\"padding:10px; text-align: left; border: 1px solid #e0e0e0;\"\u003eStock Output\u003c\/th\u003e\n\u003ctd style=\"padding:10px; border: 1px solid #e0e0e0;\"\u003e173–190 hp \/ 220–225 lb-ft\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth style=\"padding:10px; text-align: left; border: 1px solid #e0e0e0;\"\u003eReplaces OEM Part #\u003c\/th\u003e\n\u003ctd style=\"padding:10px; border: 1px solid #e0e0e0;\"\u003e3100072\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/table\u003e\n\u003c\/div\u003e\n\n\u003ch3\u003eCompatibility\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e1987-1992 Jeep Comanche (MJ) with 4.0L Inline 6-Cylinder Engine (Base, Pioneer, Chief, Laredo, Eliminator)\u003c\/li\u003e\n  \u003cli\u003eDoes not fit 2.1L Turbo-Diesel, 2.5L 4-Cylinder, or 2.8L V6 models.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\n\u003ch4\u003eDoes this fit the MJ Comanche?\u003c\/h4\u003e\n\u003cp\u003eYes, this is a direct fit for the 1987-1992 Jeep Comanche equipped with the \u003cstrong\u003eAMC 242\u003c\/strong\u003e engine.\u003c\/p\u003e\n\n\u003ch4\u003eWhich engine block location accepts this heater element?\u003c\/h4\u003e\n\u003cp\u003eIt installs directly into a standard 2-inch freeze (core) plug port along the cylinder block cooling passage.\u003c\/p\u003e\n\n\u003ch3\u003eThe Jeep Comanche Durability Standard\u003c\/h3\u003e\n\u003cp\u003eEngineered for workhorse durability and demanding haul requirements, the Comanche's cast-iron inline-six requires reliable thermal management to preserve journal bearings, reduce starter load, and maintain peak operating reliability in freezing climates.\u003c\/p\u003e","brand":"VelocityMax","offers":[{"title":"Default Title","offer_id":67539508494584,"sku":"DS-EPBS1RX5M","price":64.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0800\/1290\/2648\/files\/engine-block-heater-for-jeep-comanche-1987-1992-4-0l-1.jpg?v=1790650364","url":"https:\/\/performancechiptuning.com\/fr\/products\/engine-block-heater-for-jeep-comanche-1987-1992-4-0l","provider":"Performance Chip Tuning","version":"1.0","type":"link"}