{"product_id":"x4xz-coolant-reservoir-with-sensor-for-bmw-120i-520i-2012-2019-direct-fit-603-880-oe-replacement-thermoplastic","title":"X4XZ Coolant Reservoir with Sensor for BMW 120i–520i (2012–2019) — Direct-Fit 603-880 OE Replacement, Thermoplastic","description":"\u003cp\u003e\u003cstrong\u003eX4XZ 603-880 coolant reservoir with sensor is a direct-fit radiator expansion tank designed to replace worn or leaking reservoirs on select 2012–2019 BMW 120i through 520i models.\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cp\u003eThis replacement surge tank restores a sealed coolant circuit and provides the correct mounting and sensor connections for the listed BMW 2.0L four-cylinder models. Built from sturdy thermoplastic and tested for compatibility, the unit includes the OE-equivalent sensor mounting and cap seat to help maintain proper coolant level monitoring and pressure behavior without modifying your original plumbing.\u003c\/p\u003e\n\n\u003ch3\u003eHow will this reservoir affect my engine cooling system?\u003c\/h3\u003e\n\u003cp\u003eThe reservoir collects expanding coolant from the radiator and returns it as the system cools, preventing air pockets and maintaining level. Using a properly sized, undamaged tank keeps the closed cooling system operating as engineered and helps the coolant sensor report accurate levels to the vehicle electronics.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eReplaces OE# 603-880 and OEM references 17137642158, 17137609469.\u003c\/li\u003e\n  \u003cli\u003eIncludes integrated sensor mounting for original wiring compatibility.\u003c\/li\u003e\n  \u003cli\u003eMolded ports match factory hose locations — no cutting or splicing required.\u003c\/li\u003e\n  \u003cli\u003eResists heat and coolant fluids for long-term service life.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhich BMW models does this reservoir fit and how do I confirm compatibility?\u003c\/h3\u003e\n\u003cp\u003eThis tank was produced to fit many BMW 2.0L L4 platforms from model years 2012–2019, including various 1, 2, 3, 4 and 5 Series variants. Confirm fit by matching part numbers or comparing mounting points and sensor connector shape with your original tank.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eFits: 120i (F20), 220i (F22\/F23), 228i (F22\/F23), 320i\/320i xDrive (F30), 328i\/328i xDrive\/GT (F30\/F31\/F34), 420i\/428i (F32\/F33\/F36), 520i models listed.\u003c\/li\u003e\n  \u003cli\u003eCross-check OE numbers 17137642158 and 17137609469 to verify match.\u003c\/li\u003e\n  \u003cli\u003eInspect hose locations and sensor plug shape before purchase.\u003c\/li\u003e\n  \u003cli\u003eRefer to model and year combinations in the product details list for clarity.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhat are the benefits of replacing a damaged reservoir with this unit?\u003c\/h3\u003e\n\u003cp\u003eSwapping a cracked or leaking tank stops coolant loss, prevents engine overheating risk due to low level, and restores proper sensor readings. A new, correctly fitted reservoir also reduces the chance of vapor lock and helps preserve thermostat and head gasket longevity by maintaining correct system pressure behavior.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eSeals coolant system to prevent leaks and contamination.\u003c\/li\u003e\n  \u003cli\u003eRestores accurate coolant-level sensing for dashboard warnings.\u003c\/li\u003e\n  \u003cli\u003eDurable construction reduces repeat replacements.\u003c\/li\u003e\n  \u003cli\u003eDirect-fit design minimizes installation time and complexity.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eHow difficult is installation and what comes in the package?\u003c\/h3\u003e\n\u003cp\u003eInstallation is straightforward for anyone familiar with simple engine-bay repairs: remove the old tank, swap hoses and sensor connector, and secure the new unit into factory mounting points. Hardware and cap seat are provided as part of the molded assembly; basic hand tools and coolant top-up are all that’s typically required.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003ePackage contains one complete coolant reservoir (cap included in seat).\u003c\/li\u003e\n  \u003cli\u003eNo printed manual included — basic mechanical skill recommended.\u003c\/li\u003e\n  \u003cli\u003eAfter installation, bleed the cooling system and check for leaks.\u003c\/li\u003e\n  \u003cli\u003eX4XZ provides 24-hour customer support and a 1-year product service period.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eWho is this for: This X4XZ 603-880 coolant reservoir is intended for BMW owners, independent mechanics, and repair shops maintaining 2012–2019 BMW 120i, 220i, 228i, 320i\/328i, 420i\/428i, and 520i models with the 2.0L L4 engines. Choose this part if you need a direct-fit replacement with the correct sensor interface and OEM-equivalent references for a reliable, like-for-like restoration of your vehicle’s cooling circuit.\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: Does this reservoir include the coolant cap?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: Yes, the molded assembly includes the cap seat and cap; no separate cap purchase is required.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: Can I use this part on a turbocharged BMW model?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: This reservoir fits the specific 2.0L L4 BMW models listed; check OE cross-reference numbers to confirm turbo model compatibility.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/section\u003e","brand":"X4XZ","offers":[{"title":"Default Title","offer_id":48083022971038,"sku":"B0F5Q54S6H","price":60.48,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0781\/2041\/9486\/files\/x4xz-coolant-reservoir-front-view.jpg?v=1785822879","url":"https:\/\/northtrailauto.ca\/products\/x4xz-coolant-reservoir-with-sensor-for-bmw-120i-520i-2012-2019-direct-fit-603-880-oe-replacement-thermoplastic","provider":"North Trail Auto","version":"1.0","type":"link"}