Discover Toyota Sienna Engine Block Heaters & Toyota Sienna Block Heaters For Cars. Shop Toyota Sienna Car Block Heaters. Maintaining your Toyota Sienna's engine block heater can significantly improve cold starts and prolong engine life, especially in harsh winters. Regularly inspect the heater for wear and corrosion, and ensure it's properly secured to prevent damage. If you notice slower engine warm-ups or no warmth at all, it's time to consider a replacement. When selecting a new heater, opt for either freeze plug, bolt-on, or oil pan heaters, each designed for efficient heat transfer and tailored to fit your Sienna's specifications. For enhanced durability, choose heaters made from high-quality materials and follow the manufacturer's installation guidelines to ensure optimal performance. Keep these tips in mind to maximize the longevity of your engine block heater and maintain your Sienna's reliability even in the coldest conditions.