Air and Fuel› Oxygen Sensors, Controllers and Components

GM

4-Bar MAP Sensor

$18.00

SKU: 12643955

In Stock
In Stock
Ships by Sep 12
Free Shipping over $200
$100 Minimum Order
30 Days Return
INSTALL DIFFICULTY
DIY PRO SHOP

Beginner — under 30 min

Overview

The Genuine GM 12643955 is a 4-Bar MAP sensor designed to accurately read boost pressure up to 44 psi. This sensor supersedes part number 25203477 and is engineered for durability and precise readings in high-boost applications.

It is a direct-fit replacement for factory 1 or 2-bar MAP sensors on various GM vehicles, requiring no cutting or splicing for installation. The sensor is compatible with intake manifolds featuring "LS3" style MAP sensor ports.
Show original supplier description
The Genuine GM 12643955 is a 4-Bar Manifold Absolute Pressure (MAP) sensor, engineered to provide accurate boost readings up to 44 psi. This genuine factory part supersedes the GM part number 25203477, offering enhanced durability and precision for forced induction systems. This sensor is designed as a direct-fit replacement for factory 1-bar or 2-bar MAP sensors on compatible GM vehicles, eliminating the need for cutting or splicing wires. It is particularly suited for intake manifolds equipped with "LS3" style MAP sensor ports. The sensor is also noted as a direct-fit for GM 6.6 L Duramax engines and is used on 2011-2016 Chevy/GMC 2500HD/3500HD trucks with the 6.6-liter Duramax diesel engine. While designed for ease of installation on specific GM platforms, it is important to note that utilizing a 4-Bar MAP sensor often requires corresponding PCM tuning and proper sensor data scaling in kPa to ensure correct calibration and operation. This sensor is not typically considered a performance part in itself but rather an upgrade component that enables higher boost monitoring capabilities when used in conjunction with other performance modifications and tuning. This part is listed as having universal fitment in some contexts but is otherwise specified as a "Specific" vehicle fitment type. It supersedes GM part number 25203477.

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.

Fitment

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Specifications

BrandGM
Part Number12643955
CategoryAir and Fuel

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Shipping

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