Is Your GM Vehicle Running Rough? The ECM Might Be the Culprit.
Are you dealing with a persistent Check Engine Light, unexplained stalling, poor fuel mileage, or a vehicle that simply won’t start? These frustrating and often confusing issues can frequently be traced back to a single, critical component: the Engine Control Module (ECM). As the central computer for your engine, a failing ECM can cause a wide range of performance problems, leaving you stranded and facing a costly trip to the dealership. This pre-programmed ECM, part number 12667002, is the reliable, cost-effective solution to get your vehicle back on the road and running like new.
From the Diagnostic Bay
We had a 2018 Chevy Impala come into the shop with a problem that was driving the owner crazy. The car would randomly stall at stoplights, but not every time. There were no consistent trouble codes stored, making diagnosis a real challenge. After checking all the usual suspects—fuel pressure, sensors, wiring—we hooked up our advanced scanner to monitor live data. We noticed that just before a stall, the processor load on the original ECM would spike and several key sensor readings would flicker erratically. It was clear the module’s internal logic was failing under certain conditions. We installed one of our VIN-programmed ECMs, performed the quick security relearn, and the car ran perfectly. The ghost in the machine was gone, and the customer was thrilled to have their reliable car back without a massive dealership bill.
Common Symptoms of a Failing ECM
- ✔ Persistent Check Engine Light (CEL) that won’t clear.
- ✔ Engine stalling or shutting off unexpectedly while driving.
- ✔ Rough idling, hesitation, or misfires.
- ✔ A noticeable drop in fuel economy.
- ✔ The vehicle cranks but refuses to start (no-start condition).
- ✔ Transmission shifting problems or harsh shifts.
- ✔ Inability to communicate with the module using a diagnostic scan tool.
Why Choose Our Pre-Programmed 2017-2019 GM ECM?
Replacing an ECM isn’t just about swapping parts. Modern vehicle computers are complex and must be specifically coded to your car’s unique Vehicle Identification Number (VIN). Our service eliminates the most difficult part of the job. When you order from us, you provide your VIN, and we flash the module with the latest, most up-to-date software directly from GM. This ensures that the ECM is perfectly matched to your vehicle’s specific options, emissions system, and powertrain configuration. This is not a generic, one-size-fits-all solution; it’s a tailored fix for your exact car or truck.
This module is a direct replacement for part numbers 12667002, 12666070, and 12667189. By purchasing our pre-programmed 2017-2019 GM ECM, you are getting a component that is ready for installation right out of the box, saving you hundreds of dollars in programming fees and towing costs associated with a dealership visit.
Installation and Setup
While the physical installation is straightforward for a competent DIY mechanic, please note that after installation, you may need to perform a security relearn procedure (also known as a Passlock or anti-theft relearn). This procedure pairs the new ECM to your vehicle’s existing anti-theft system and keys. In many GM vehicles, this is a simple process that can be done in your driveway without any special tools. Instructions are widely available online, or your local mechanic can perform it quickly.
Guaranteed Fitment
This ECM is compatible with a wide range of popular GM vehicles. Please verify your model and options below:
- Cadillac XTS: 2017-2019 (3.6L, VIN 3 – 8th digit, opt LFX)
- Chevrolet Caprice: 2017 (3.6L)
- Chevrolet Traverse: 2017
- Chevrolet Impala: 2017-2019
- Chevrolet Equinox: 2017
- GMC Acadia: 2017 (Limited, VIN J – 11th digit)
- GMC Terrain: 2017
- Buick Enclave: 2017
- Buick Regal: 2017
- Buick Verano: 2017
Frequently Asked Questions
Why do I need to provide my VIN?
Your vehicle’s VIN (Vehicle Identification Number) is essential. It allows us to load the exact GM-specified software and calibrations for your car’s engine, transmission, and factory options. This ensures perfect compatibility and performance, avoiding the need for expensive dealership programming.
Is this part difficult to install?
The physical replacement is typically simple, involving disconnecting the battery, unplugging a few electrical connectors, and unbolting the old module. The most important step after installation is the security relearn procedure, which syncs the new ECM to your car’s anti-theft system. This can often be done without special tools.
Will this fix my car’s specific problem?
This ECM will resolve issues directly caused by a faulty engine computer. While the symptoms listed above are common indicators of ECM failure, it’s crucial to have your vehicle properly diagnosed by a qualified mechanic to rule out other potential causes like bad sensors or wiring issues.
What’s the difference between an ECM, ECU, and PCM?
The terms are often used interchangeably. ECM (Engine Control Module) and ECU (Engine Control Unit) refer to the same computer. PCM (Powertrain Control Module) is a more integrated unit that controls both the engine and the transmission. For your vehicle, this part serves as the central engine computer.
What happens if I don’t perform the security relearn?
If the security relearn procedure is required and not completed, your vehicle’s anti-theft system will likely prevent the engine from starting. It’s a critical step to ensure the new module is accepted by the vehicle’s security network.