Is Your Buick Encore Running Rough? The ECM Might Be the Culprit.
The Engine Control Module (ECM), often called the vehicle’s brain, is the master computer responsible for managing your engine’s performance, fuel efficiency, and emissions. When it starts to fail in your 2013-2016 Buick Encore, it can cause a cascade of confusing and frustrating problems, from a simple check engine light to a car that won’t start at all. This replacement Engine Control Module, part number 12670335, is the definitive solution to restore your vehicle’s factory performance and reliability.
Unlike a generic module from a parts store, this ECM comes fully programmed to your vehicle’s specific Vehicle Identification Number (VIN). We load the latest, most stable software updates directly from GM before it ships. This critical step ensures seamless communication with your vehicle’s other electronic systems, eliminating the need for an expensive trip to the dealership for programming. It’s a true plug-and-play solution designed to get you back on the road quickly and confidently.
From the Diagnostic Bay
We had a 2014 Encore come into the shop with a list of bizarre symptoms. The owner complained of intermittent stalling at red lights, poor acceleration, and a check engine light that would come and go. The codes were all over the place—misfires, O2 sensor faults, and even a transmission communication error. After hours of chasing down potential sensor and wiring issues, we finally focused on the ECM. Once we swapped in a VIN-programmed module, every single issue vanished. The car ran smoother than ever. It’s a classic case of how a failing ECM can send you on a wild goose chase, making a pre-programmed, direct-fit part the smartest and most efficient repair.
Why Choose a VIN-Programmed 2013-2016 Encore ECM?
Your Buick Encore is a complex machine with dozens of sensors and modules that need to work in perfect harmony. The ECM is the conductor of this orchestra. By providing us with your VIN, you guarantee that the module you receive is calibrated for your exact engine, transmission, and emissions equipment. This eliminates compatibility guesswork and prevents potential performance issues that can arise from using a non-programmed or incorrectly programmed computer. This module is a direct replacement for a wide range of original part numbers, including 12668866, 12668994, 12643636, and more, ensuring broad compatibility across many GM vehicles.
Common Symptoms of a Failing ECM
- ✔ Persistent Check Engine Light (CEL) that won’t clear or returns immediately.
- ✔ Engine stalling, stumbling, or hesitating during acceleration.
- ✔ Noticeable decrease in fuel economy (MPG).
- ✔ Rough or erratic automatic transmission shifting.
- ✔ The engine cranks but refuses to start (no-start condition).
- ✔ Misfire codes (e.g., P0300, P0301) even after replacing plugs and coils.
- ✔ Failure to pass state emissions testing.
- ✔ Loss of communication with diagnostic scan tools.
Broad Compatibility Beyond the Encore
While this is the primary computer for the 2013-2016 Encore ECM, its versatile architecture means it’s also the correct fit for an extensive list of other popular GM models. This includes the Chevrolet Cruze (2012-2016), Sonic (2012-2016), Trax (2013-2016), and even heavy-duty vehicles like the Silverado/Sierra 2500/3500 pickups (2012-2016) with the 6.0L engine, and Express/Savana vans. This cross-compatibility is a testament to its robust design and our VIN-specific programming ensures it functions perfectly no matter the application.
Installation Process
Replacing the ECM is a straightforward process for a seasoned DIYer or any professional mechanic. The module is typically located in the engine bay. The basic steps involve disconnecting the vehicle’s battery, carefully unplugging the wiring harnesses from the old module, unbolting it from its bracket, and then installing the new one in the reverse order. Once installed and the battery is reconnected, you may need to perform a simple security relearn or Crankshaft Variation (CASE) relearn procedure, which can often be done without special tools. However, for peace of mind, professional installation is always recommended.
Frequently Asked Questions
Do I need to get this ECM programmed by a dealer?
No. This is the biggest benefit of our service. We program the module with the latest GM software using the VIN you provide during checkout. It will arrive at your door ready to be installed, saving you time and the high cost of dealership programming.
Where is the ECM located on my 2014 Buick Encore?
On most 2013-2016 Buick Encore models, the Engine Control Module is located in the engine compartment, typically mounted near the battery or on the firewall. Always disconnect the battery before attempting to access or replace it.
Will this fix my check engine light?
If the check engine light and associated diagnostic trouble codes (DTCs) are being caused by a faulty ECM, then yes, this part will resolve the issue. It is crucial to have the vehicle properly diagnosed to confirm the ECM is the point of failure before ordering.
What is a CASE relearn and is it required?
A Crankshaft Position System Variation (CASE) relearn synchronizes the new ECM with the engine’s crankshaft position sensor. After installation, some vehicles may require this procedure to clear certain trouble codes and ensure optimal engine timing. Many modern scan tools can perform this function, and some vehicles can even initiate it with a specific driving cycle.
How do I provide my VIN?
After you complete your purchase, we will send you an email requesting your vehicle’s 17-digit VIN. You can also add it to the notes section during checkout. We cannot ship your part until we have the VIN to program it correctly.
Is this part compatible with a Chevy Cruze or Sonic?
Yes, this ECM (part number 12670335 and its alternates) is the correct module for many other GM vehicles, including the Chevy Cruze, Sonic, Trax, Volt, and even some Express/Savana vans and Silverado/Sierra trucks. Our VIN-specific programming ensures it works perfectly for your application.