Ignitions and Electrical› Computers, Chips, Modules and Programmers

RENNtech

ECU Upgrade Performance Tuning Module

$965.15

SKU: 54.211.E350

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$100 Minimum Order
Non-Returnable Item
INSTALL DIFFICULTY
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Overview

The RENNtech ECU Upgrade is an engine control unit modification designed for the E 350 W211. It increases performance to 290 horsepower and 278 lb-ft of torque. This upgrade modifies ignition timing, throttle mapping, air/fuel ratios, and the engine's rev limiter to unleash the vehicle's potential.
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The RENNtech Performance ECU Upgrade, utilizing the HHT (handheld tuner) system, offers a seamless way to enhance your Mercedes-Benz W211 E350. This module allows for unlimited switching between the RENNtech tuned file and your vehicle's original stock file, eliminating the need to remove the ECU. Simply plug the module into your OBD2 port, and the programming process takes only a few minutes. You can reflash your vehicle as many times as you desire. By precisely adjusting ignition timing, throttle mapping, and air/fuel ratios, and by increasing the engine's rev limiter and optimizing boost mapping for turbocharged models, this upgrade unlocks your Mercedes' latent performance capabilities. The result is an exhilarating driving experience with noticeable improvements in acceleration and responsiveness. The stock performance of the Mercedes-Benz W211 E350 is rated at 268 HP and 258 LB-FT of torque. After installation of the RENNtech ECU Upgrade, modified performance is stated to reach 290 HP and 278 LB-FT of torque. This represents an increase of +22 HP and +20 LB-FT. This ECU upgrade is specifically designed for the 2003 through 2009 Mercedes-Benz W211 E350 models.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

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Specifications

BrandRENNtech
Part Number54.211.E350
CategoryIgnitions and Electrical
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Returns & Fitment

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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